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-rw-r--r--synapse/__init__.py2
-rw-r--r--synapse/api/auth.py6
-rw-r--r--synapse/api/errors.py16
-rw-r--r--synapse/app/_base.py25
-rw-r--r--synapse/app/frontend_proxy.py10
-rwxr-xr-xsynapse/app/homeserver.py137
-rw-r--r--synapse/app/media_repository.py10
-rw-r--r--synapse/app/synchrotron.py9
-rw-r--r--synapse/appservice/__init__.py37
-rw-r--r--synapse/appservice/api.py10
-rw-r--r--synapse/appservice/scheduler.py2
-rw-r--r--synapse/config/_base.py36
-rw-r--r--synapse/config/appservice.py1
-rw-r--r--synapse/config/cas.py2
-rw-r--r--synapse/config/groups.py32
-rw-r--r--synapse/config/homeserver.py4
-rw-r--r--synapse/config/key.py8
-rw-r--r--synapse/config/logger.py6
-rw-r--r--synapse/config/password_auth_providers.py39
-rw-r--r--synapse/config/push.py44
-rw-r--r--synapse/config/registration.py7
-rw-r--r--synapse/config/repository.py20
-rw-r--r--synapse/config/server.py15
-rw-r--r--synapse/config/tls.py12
-rw-r--r--synapse/config/user_directory.py44
-rw-r--r--synapse/crypto/context_factory.py2
-rw-r--r--synapse/crypto/event_signing.py15
-rw-r--r--synapse/crypto/keyring.py2
-rw-r--r--synapse/event_auth.py10
-rw-r--r--synapse/events/builder.py2
-rw-r--r--synapse/events/spamcheck.py68
-rw-r--r--synapse/federation/federation_client.py4
-rw-r--r--synapse/federation/federation_server.py174
-rw-r--r--synapse/federation/transaction_queue.py56
-rw-r--r--synapse/federation/transport/client.py415
-rw-r--r--synapse/federation/transport/server.py572
-rw-r--r--synapse/groups/__init__.py0
-rw-r--r--synapse/groups/attestations.py195
-rw-r--r--synapse/groups/groups_server.py864
-rw-r--r--synapse/handlers/__init__.py2
-rw-r--r--synapse/handlers/appservice.py10
-rw-r--r--synapse/handlers/auth.py413
-rw-r--r--synapse/handlers/deactivate_account.py52
-rw-r--r--synapse/handlers/device.py27
-rw-r--r--synapse/handlers/directory.py15
-rw-r--r--synapse/handlers/federation.py163
-rw-r--r--synapse/handlers/groups_local.py429
-rw-r--r--synapse/handlers/initial_sync.py6
-rw-r--r--synapse/handlers/message.py52
-rw-r--r--synapse/handlers/presence.py4
-rw-r--r--synapse/handlers/profile.py142
-rw-r--r--synapse/handlers/receipts.py4
-rw-r--r--synapse/handlers/register.py32
-rw-r--r--synapse/handlers/room.py24
-rw-r--r--synapse/handlers/room_list.py77
-rw-r--r--synapse/handlers/room_member.py27
-rw-r--r--synapse/handlers/search.py2
-rw-r--r--synapse/handlers/set_password.py56
-rw-r--r--synapse/handlers/sync.py71
-rw-r--r--synapse/handlers/user_directory.py76
-rw-r--r--synapse/http/additional_resource.py55
-rw-r--r--synapse/http/client.py127
-rw-r--r--synapse/http/endpoint.py28
-rw-r--r--synapse/http/matrixfederationclient.py85
-rw-r--r--synapse/http/server.py18
-rw-r--r--synapse/http/servlet.py9
-rw-r--r--synapse/http/site.py2
-rw-r--r--synapse/module_api/__init__.py123
-rw-r--r--synapse/notifier.py19
-rw-r--r--synapse/push/baserules.py23
-rw-r--r--synapse/push/bulk_push_rule_evaluator.py35
-rw-r--r--synapse/push/emailpusher.py2
-rw-r--r--synapse/push/httppusher.py9
-rw-r--r--synapse/push/push_rule_evaluator.py50
-rw-r--r--synapse/push/pusher.py2
-rw-r--r--synapse/push/pusherpool.py36
-rw-r--r--synapse/python_dependencies.py4
-rw-r--r--synapse/replication/slave/storage/_base.py2
-rw-r--r--synapse/replication/slave/storage/events.py39
-rw-r--r--synapse/replication/slave/storage/groups.py54
-rw-r--r--synapse/replication/tcp/resource.py12
-rw-r--r--synapse/replication/tcp/streams.py20
-rw-r--r--synapse/rest/__init__.py2
-rw-r--r--synapse/rest/client/v1/admin.py13
-rw-r--r--synapse/rest/client/v1/directory.py2
-rw-r--r--synapse/rest/client/v1/login.py75
-rw-r--r--synapse/rest/client/v1/logout.py33
-rw-r--r--synapse/rest/client/v1/presence.py2
-rw-r--r--synapse/rest/client/v1/profile.py22
-rw-r--r--synapse/rest/client/v1/register.py2
-rw-r--r--synapse/rest/client/v1/room.py9
-rw-r--r--synapse/rest/client/v2_alpha/_base.py41
-rw-r--r--synapse/rest/client/v2_alpha/account.py149
-rw-r--r--synapse/rest/client/v2_alpha/devices.py40
-rw-r--r--synapse/rest/client/v2_alpha/filter.py2
-rw-r--r--synapse/rest/client/v2_alpha/groups.py758
-rw-r--r--synapse/rest/client/v2_alpha/keys.py18
-rw-r--r--synapse/rest/client/v2_alpha/notifications.py2
-rw-r--r--synapse/rest/client/v2_alpha/register.py101
-rw-r--r--synapse/rest/client/v2_alpha/sendtodevice.py2
-rw-r--r--synapse/rest/client/v2_alpha/sync.py7
-rw-r--r--synapse/rest/client/v2_alpha/thirdparty.py11
-rw-r--r--synapse/rest/client/v2_alpha/user_directory.py2
-rw-r--r--synapse/rest/client/versions.py1
-rw-r--r--synapse/rest/key/v2/remote_key_resource.py2
-rw-r--r--synapse/rest/media/v1/_base.py7
-rw-r--r--synapse/rest/media/v1/filepath.py176
-rw-r--r--synapse/rest/media/v1/media_repository.py373
-rw-r--r--synapse/rest/media/v1/preview_url_resource.py218
-rw-r--r--synapse/rest/media/v1/thumbnailer.py25
-rw-r--r--synapse/rest/media/v1/upload_resource.py2
-rw-r--r--synapse/server.py80
-rw-r--r--synapse/server.pyi26
-rw-r--r--synapse/state.py15
-rw-r--r--synapse/storage/__init__.py20
-rw-r--r--synapse/storage/_base.py154
-rw-r--r--synapse/storage/account_data.py87
-rw-r--r--synapse/storage/appservice.py8
-rw-r--r--synapse/storage/background_updates.py41
-rw-r--r--synapse/storage/client_ips.py4
-rw-r--r--synapse/storage/deviceinbox.py4
-rw-r--r--synapse/storage/devices.py4
-rw-r--r--synapse/storage/event_federation.py4
-rw-r--r--synapse/storage/event_push_actions.py4
-rw-r--r--synapse/storage/events.py33
-rw-r--r--synapse/storage/group_server.py1233
-rw-r--r--synapse/storage/media_repository.py93
-rw-r--r--synapse/storage/prepare_database.py74
-rw-r--r--synapse/storage/profile.py125
-rw-r--r--synapse/storage/pusher.py76
-rw-r--r--synapse/storage/receipts.py4
-rw-r--r--synapse/storage/registration.py55
-rw-r--r--synapse/storage/roommember.py46
-rw-r--r--synapse/storage/schema/delta/30/as_users.py2
-rw-r--r--synapse/storage/schema/delta/43/user_share.sql2
-rw-r--r--synapse/storage/schema/delta/44/expire_url_cache.sql41
-rw-r--r--synapse/storage/schema/delta/45/group_server.sql167
-rw-r--r--synapse/storage/schema/delta/45/profile_cache.sql (renamed from synapse/storage/schema/delta/23/refresh_tokens.sql)17
-rw-r--r--synapse/storage/schema/delta/46/drop_refresh_tokens.sql (renamed from synapse/storage/schema/delta/33/refreshtoken_device.sql)5
-rw-r--r--synapse/storage/schema/delta/46/drop_unique_deleted_pushers.sql35
-rw-r--r--synapse/storage/schema/delta/46/group_server.sql32
-rw-r--r--synapse/storage/schema/delta/46/local_media_repository_url_idx.sql (renamed from synapse/storage/schema/delta/33/refreshtoken_device_index.sql)11
-rw-r--r--synapse/storage/schema/delta/46/user_dir_null_room_ids.sql35
-rw-r--r--synapse/storage/schema/delta/46/user_dir_typos.sql24
-rw-r--r--synapse/storage/schema/schema_version.sql7
-rw-r--r--synapse/storage/search.py8
-rw-r--r--synapse/storage/state.py443
-rw-r--r--synapse/storage/stream.py4
-rw-r--r--synapse/storage/transactions.py4
-rw-r--r--synapse/storage/user_directory.py64
-rw-r--r--synapse/streams/config.py6
-rw-r--r--synapse/streams/events.py4
-rw-r--r--synapse/types.py52
-rw-r--r--synapse/util/__init__.py18
-rw-r--r--synapse/util/async.py69
-rw-r--r--synapse/util/distributor.py22
-rw-r--r--synapse/util/logcontext.py63
-rw-r--r--synapse/util/logformatter.py51
-rw-r--r--synapse/util/retryutils.py2
-rw-r--r--synapse/util/wheel_timer.py5
-rw-r--r--synapse/visibility.py4
161 files changed, 9103 insertions, 1732 deletions
diff --git a/synapse/__init__.py b/synapse/__init__.py
index ec83e6adb7..ef8853bd24 100644
--- a/synapse/__init__.py
+++ b/synapse/__init__.py
@@ -16,4 +16,4 @@
 """ This is a reference implementation of a Matrix home server.
 """
 
-__version__ = "0.23.0-rc2"
+__version__ = "0.26.0"
diff --git a/synapse/api/auth.py b/synapse/api/auth.py
index 72858cca1f..ac0a3655a5 100644
--- a/synapse/api/auth.py
+++ b/synapse/api/auth.py
@@ -270,7 +270,11 @@ class Auth(object):
             rights (str): The operation being performed; the access token must
                 allow this.
         Returns:
-            dict : dict that includes the user and the ID of their access token.
+            Deferred[dict]: dict that includes:
+               `user` (UserID)
+               `is_guest` (bool)
+               `token_id` (int|None): access token id. May be None if guest
+               `device_id` (str|None): device corresponding to access token
         Raises:
             AuthError if no user by that token exists or the token is invalid.
         """
diff --git a/synapse/api/errors.py b/synapse/api/errors.py
index d0dfa959dc..79b35b3e7c 100644
--- a/synapse/api/errors.py
+++ b/synapse/api/errors.py
@@ -140,6 +140,22 @@ class RegistrationError(SynapseError):
     pass
 
 
+class InteractiveAuthIncompleteError(Exception):
+    """An error raised when UI auth is not yet complete
+
+    (This indicates we should return a 401 with 'result' as the body)
+
+    Attributes:
+        result (dict): the server response to the request, which should be
+            passed back to the client
+    """
+    def __init__(self, result):
+        super(InteractiveAuthIncompleteError, self).__init__(
+            "Interactive auth not yet complete",
+        )
+        self.result = result
+
+
 class UnrecognizedRequestError(SynapseError):
     """An error indicating we don't understand the request you're trying to make"""
     def __init__(self, *args, **kwargs):
diff --git a/synapse/app/_base.py b/synapse/app/_base.py
index cd0e815919..9477737759 100644
--- a/synapse/app/_base.py
+++ b/synapse/app/_base.py
@@ -12,10 +12,16 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
+
 import gc
 import logging
+import sys
+
+try:
+    import affinity
+except Exception:
+    affinity = None
 
-import affinity
 from daemonize import Daemonize
 from synapse.util import PreserveLoggingContext
 from synapse.util.rlimit import change_resource_limit
@@ -78,6 +84,13 @@ def start_reactor(
         with PreserveLoggingContext():
             logger.info("Running")
             if cpu_affinity is not None:
+                if not affinity:
+                    quit_with_error(
+                        "Missing package 'affinity' required for cpu_affinity\n"
+                        "option\n\n"
+                        "Install by running:\n\n"
+                        "   pip install affinity\n\n"
+                    )
                 logger.info("Setting CPU affinity to %s" % cpu_affinity)
                 affinity.set_process_affinity_mask(0, cpu_affinity)
             change_resource_limit(soft_file_limit)
@@ -97,3 +110,13 @@ def start_reactor(
         daemon.start()
     else:
         run()
+
+
+def quit_with_error(error_string):
+    message_lines = error_string.split("\n")
+    line_length = max([len(l) for l in message_lines if len(l) < 80]) + 2
+    sys.stderr.write("*" * line_length + '\n')
+    for line in message_lines:
+        sys.stderr.write(" %s\n" % (line.rstrip(),))
+    sys.stderr.write("*" * line_length + '\n')
+    sys.exit(1)
diff --git a/synapse/app/frontend_proxy.py b/synapse/app/frontend_proxy.py
index bee4c47498..abc7ef5725 100644
--- a/synapse/app/frontend_proxy.py
+++ b/synapse/app/frontend_proxy.py
@@ -50,8 +50,7 @@ logger = logging.getLogger("synapse.app.frontend_proxy")
 
 
 class KeyUploadServlet(RestServlet):
-    PATTERNS = client_v2_patterns("/keys/upload(/(?P<device_id>[^/]+))?$",
-                                  releases=())
+    PATTERNS = client_v2_patterns("/keys/upload(/(?P<device_id>[^/]+))?$")
 
     def __init__(self, hs):
         """
@@ -89,9 +88,16 @@ class KeyUploadServlet(RestServlet):
 
         if body:
             # They're actually trying to upload something, proxy to main synapse.
+            # Pass through the auth headers, if any, in case the access token
+            # is there.
+            auth_headers = request.requestHeaders.getRawHeaders("Authorization", [])
+            headers = {
+                "Authorization": auth_headers,
+            }
             result = yield self.http_client.post_json_get_json(
                 self.main_uri + request.uri,
                 body,
+                headers=headers,
             )
 
             defer.returnValue((200, result))
diff --git a/synapse/app/homeserver.py b/synapse/app/homeserver.py
index 84ad8f04a0..6b8875afb4 100755
--- a/synapse/app/homeserver.py
+++ b/synapse/app/homeserver.py
@@ -25,10 +25,13 @@ from synapse.api.urls import CONTENT_REPO_PREFIX, FEDERATION_PREFIX, \
     LEGACY_MEDIA_PREFIX, MEDIA_PREFIX, SERVER_KEY_PREFIX, SERVER_KEY_V2_PREFIX, \
     STATIC_PREFIX, WEB_CLIENT_PREFIX
 from synapse.app import _base
+from synapse.app._base import quit_with_error
 from synapse.config._base import ConfigError
 from synapse.config.homeserver import HomeServerConfig
 from synapse.crypto import context_factory
 from synapse.federation.transport.server import TransportLayerServer
+from synapse.module_api import ModuleApi
+from synapse.http.additional_resource import AdditionalResource
 from synapse.http.server import RootRedirect
 from synapse.http.site import SynapseSite
 from synapse.metrics import register_memory_metrics
@@ -40,7 +43,6 @@ from synapse.rest import ClientRestResource
 from synapse.rest.key.v1.server_key_resource import LocalKey
 from synapse.rest.key.v2 import KeyApiV2Resource
 from synapse.rest.media.v0.content_repository import ContentRepoResource
-from synapse.rest.media.v1.media_repository import MediaRepositoryResource
 from synapse.server import HomeServer
 from synapse.storage import are_all_users_on_domain
 from synapse.storage.engines import IncorrectDatabaseSetup, create_engine
@@ -48,6 +50,7 @@ from synapse.storage.prepare_database import UpgradeDatabaseException, prepare_d
 from synapse.util.httpresourcetree import create_resource_tree
 from synapse.util.logcontext import LoggingContext
 from synapse.util.manhole import manhole
+from synapse.util.module_loader import load_module
 from synapse.util.rlimit import change_resource_limit
 from synapse.util.versionstring import get_version_string
 from twisted.application import service
@@ -106,52 +109,18 @@ class SynapseHomeServer(HomeServer):
         resources = {}
         for res in listener_config["resources"]:
             for name in res["names"]:
-                if name == "client":
-                    client_resource = ClientRestResource(self)
-                    if res["compress"]:
-                        client_resource = gz_wrap(client_resource)
-
-                    resources.update({
-                        "/_matrix/client/api/v1": client_resource,
-                        "/_matrix/client/r0": client_resource,
-                        "/_matrix/client/unstable": client_resource,
-                        "/_matrix/client/v2_alpha": client_resource,
-                        "/_matrix/client/versions": client_resource,
-                    })
-
-                if name == "federation":
-                    resources.update({
-                        FEDERATION_PREFIX: TransportLayerServer(self),
-                    })
-
-                if name in ["static", "client"]:
-                    resources.update({
-                        STATIC_PREFIX: File(
-                            os.path.join(os.path.dirname(synapse.__file__), "static")
-                        ),
-                    })
-
-                if name in ["media", "federation", "client"]:
-                    media_repo = MediaRepositoryResource(self)
-                    resources.update({
-                        MEDIA_PREFIX: media_repo,
-                        LEGACY_MEDIA_PREFIX: media_repo,
-                        CONTENT_REPO_PREFIX: ContentRepoResource(
-                            self, self.config.uploads_path
-                        ),
-                    })
-
-                if name in ["keys", "federation"]:
-                    resources.update({
-                        SERVER_KEY_PREFIX: LocalKey(self),
-                        SERVER_KEY_V2_PREFIX: KeyApiV2Resource(self),
-                    })
-
-                if name == "webclient":
-                    resources[WEB_CLIENT_PREFIX] = build_resource_for_web_client(self)
+                resources.update(self._configure_named_resource(
+                    name, res.get("compress", False),
+                ))
 
-                if name == "metrics" and self.get_config().enable_metrics:
-                    resources[METRICS_PREFIX] = MetricsResource(self)
+        additional_resources = listener_config.get("additional_resources", {})
+        logger.debug("Configuring additional resources: %r",
+                     additional_resources)
+        module_api = ModuleApi(self, self.get_auth_handler())
+        for path, resmodule in additional_resources.items():
+            handler_cls, config = load_module(resmodule)
+            handler = handler_cls(config, module_api)
+            resources[path] = AdditionalResource(self, handler.handle_request)
 
         if WEB_CLIENT_PREFIX in resources:
             root_resource = RootRedirect(WEB_CLIENT_PREFIX)
@@ -187,6 +156,72 @@ class SynapseHomeServer(HomeServer):
                 )
         logger.info("Synapse now listening on port %d", port)
 
+    def _configure_named_resource(self, name, compress=False):
+        """Build a resource map for a named resource
+
+        Args:
+            name (str): named resource: one of "client", "federation", etc
+            compress (bool): whether to enable gzip compression for this
+                resource
+
+        Returns:
+            dict[str, Resource]: map from path to HTTP resource
+        """
+        resources = {}
+        if name == "client":
+            client_resource = ClientRestResource(self)
+            if compress:
+                client_resource = gz_wrap(client_resource)
+
+            resources.update({
+                "/_matrix/client/api/v1": client_resource,
+                "/_matrix/client/r0": client_resource,
+                "/_matrix/client/unstable": client_resource,
+                "/_matrix/client/v2_alpha": client_resource,
+                "/_matrix/client/versions": client_resource,
+            })
+
+        if name == "federation":
+            resources.update({
+                FEDERATION_PREFIX: TransportLayerServer(self),
+            })
+
+        if name in ["static", "client"]:
+            resources.update({
+                STATIC_PREFIX: File(
+                    os.path.join(os.path.dirname(synapse.__file__), "static")
+                ),
+            })
+
+        if name in ["media", "federation", "client"]:
+            if self.get_config().enable_media_repo:
+                media_repo = self.get_media_repository_resource()
+                resources.update({
+                    MEDIA_PREFIX: media_repo,
+                    LEGACY_MEDIA_PREFIX: media_repo,
+                    CONTENT_REPO_PREFIX: ContentRepoResource(
+                        self, self.config.uploads_path
+                    ),
+                })
+            elif name == "media":
+                raise ConfigError(
+                    "'media' resource conflicts with enable_media_repo=False",
+                )
+
+        if name in ["keys", "federation"]:
+            resources.update({
+                SERVER_KEY_PREFIX: LocalKey(self),
+                SERVER_KEY_V2_PREFIX: KeyApiV2Resource(self),
+            })
+
+        if name == "webclient":
+            resources[WEB_CLIENT_PREFIX] = build_resource_for_web_client(self)
+
+        if name == "metrics" and self.get_config().enable_metrics:
+            resources[METRICS_PREFIX] = MetricsResource(self)
+
+        return resources
+
     def start_listening(self):
         config = self.get_config()
 
@@ -249,16 +284,6 @@ class SynapseHomeServer(HomeServer):
         return db_conn
 
 
-def quit_with_error(error_string):
-    message_lines = error_string.split("\n")
-    line_length = max([len(l) for l in message_lines if len(l) < 80]) + 2
-    sys.stderr.write("*" * line_length + '\n')
-    for line in message_lines:
-        sys.stderr.write(" %s\n" % (line.rstrip(),))
-    sys.stderr.write("*" * line_length + '\n')
-    sys.exit(1)
-
-
 def setup(config_options):
     """
     Args:
diff --git a/synapse/app/media_repository.py b/synapse/app/media_repository.py
index 36c18bdbcb..c4e5f0965d 100644
--- a/synapse/app/media_repository.py
+++ b/synapse/app/media_repository.py
@@ -35,7 +35,6 @@ from synapse.replication.slave.storage.registration import SlavedRegistrationSto
 from synapse.replication.slave.storage.transactions import TransactionStore
 from synapse.replication.tcp.client import ReplicationClientHandler
 from synapse.rest.media.v0.content_repository import ContentRepoResource
-from synapse.rest.media.v1.media_repository import MediaRepositoryResource
 from synapse.server import HomeServer
 from synapse.storage.engines import create_engine
 from synapse.storage.media_repository import MediaRepositoryStore
@@ -89,7 +88,7 @@ class MediaRepositoryServer(HomeServer):
                 if name == "metrics":
                     resources[METRICS_PREFIX] = MetricsResource(self)
                 elif name == "media":
-                    media_repo = MediaRepositoryResource(self)
+                    media_repo = self.get_media_repository_resource()
                     resources.update({
                         MEDIA_PREFIX: media_repo,
                         LEGACY_MEDIA_PREFIX: media_repo,
@@ -151,6 +150,13 @@ def start(config_options):
 
     assert config.worker_app == "synapse.app.media_repository"
 
+    if config.enable_media_repo:
+        _base.quit_with_error(
+            "enable_media_repo must be disabled in the main synapse process\n"
+            "before the media repo can be run in a separate worker.\n"
+            "Please add ``enable_media_repo: false`` to the main config\n"
+        )
+
     setup_logging(config, use_worker_options=True)
 
     events.USE_FROZEN_DICTS = config.use_frozen_dicts
diff --git a/synapse/app/synchrotron.py b/synapse/app/synchrotron.py
index 80e4ba5336..323fddee21 100644
--- a/synapse/app/synchrotron.py
+++ b/synapse/app/synchrotron.py
@@ -40,6 +40,7 @@ from synapse.replication.slave.storage.push_rule import SlavedPushRuleStore
 from synapse.replication.slave.storage.receipts import SlavedReceiptsStore
 from synapse.replication.slave.storage.registration import SlavedRegistrationStore
 from synapse.replication.slave.storage.room import RoomStore
+from synapse.replication.slave.storage.groups import SlavedGroupServerStore
 from synapse.replication.tcp.client import ReplicationClientHandler
 from synapse.rest.client.v1 import events
 from synapse.rest.client.v1.initial_sync import InitialSyncRestServlet
@@ -69,6 +70,7 @@ class SynchrotronSlavedStore(
     SlavedRegistrationStore,
     SlavedFilteringStore,
     SlavedPresenceStore,
+    SlavedGroupServerStore,
     SlavedDeviceInboxStore,
     SlavedDeviceStore,
     SlavedClientIpStore,
@@ -338,11 +340,10 @@ class SyncReplicationHandler(ReplicationClientHandler):
 
         self.store = hs.get_datastore()
         self.typing_handler = hs.get_typing_handler()
+        # NB this is a SynchrotronPresence, not a normal PresenceHandler
         self.presence_handler = hs.get_presence_handler()
         self.notifier = hs.get_notifier()
 
-        self.presence_handler.sync_callback = self.send_user_sync
-
     def on_rdata(self, stream_name, token, rows):
         super(SyncReplicationHandler, self).on_rdata(stream_name, token, rows)
 
@@ -403,6 +404,10 @@ class SyncReplicationHandler(ReplicationClientHandler):
             )
         elif stream_name == "presence":
             yield self.presence_handler.process_replication_rows(token, rows)
+        elif stream_name == "receipts":
+            self.notifier.on_new_event(
+                "groups_key", token, users=[row.user_id for row in rows],
+            )
 
 
 def start(config_options):
diff --git a/synapse/appservice/__init__.py b/synapse/appservice/__init__.py
index b989007314..d5a7a5ce2f 100644
--- a/synapse/appservice/__init__.py
+++ b/synapse/appservice/__init__.py
@@ -14,6 +14,7 @@
 # limitations under the License.
 from synapse.api.constants import EventTypes
 from synapse.util.caches.descriptors import cachedInlineCallbacks
+from synapse.types import GroupID, get_domain_from_id
 
 from twisted.internet import defer
 
@@ -81,12 +82,13 @@ class ApplicationService(object):
     # values.
     NS_LIST = [NS_USERS, NS_ALIASES, NS_ROOMS]
 
-    def __init__(self, token, url=None, namespaces=None, hs_token=None,
+    def __init__(self, token, hostname, url=None, namespaces=None, hs_token=None,
                  sender=None, id=None, protocols=None, rate_limited=True):
         self.token = token
         self.url = url
         self.hs_token = hs_token
         self.sender = sender
+        self.server_name = hostname
         self.namespaces = self._check_namespaces(namespaces)
         self.id = id
 
@@ -125,6 +127,24 @@ class ApplicationService(object):
                     raise ValueError(
                         "Expected bool for 'exclusive' in ns '%s'" % ns
                     )
+                group_id = regex_obj.get("group_id")
+                if group_id:
+                    if not isinstance(group_id, str):
+                        raise ValueError(
+                            "Expected string for 'group_id' in ns '%s'" % ns
+                        )
+                    try:
+                        GroupID.from_string(group_id)
+                    except Exception:
+                        raise ValueError(
+                            "Expected valid group ID for 'group_id' in ns '%s'" % ns
+                        )
+
+                    if get_domain_from_id(group_id) != self.server_name:
+                        raise ValueError(
+                            "Expected 'group_id' to be this host in ns '%s'" % ns
+                        )
+
                 regex = regex_obj.get("regex")
                 if isinstance(regex, basestring):
                     regex_obj["regex"] = re.compile(regex)  # Pre-compile regex
@@ -251,6 +271,21 @@ class ApplicationService(object):
             if regex_obj["exclusive"]
         ]
 
+    def get_groups_for_user(self, user_id):
+        """Get the groups that this user is associated with by this AS
+
+        Args:
+            user_id (str): The ID of the user.
+
+        Returns:
+            iterable[str]: an iterable that yields group_id strings.
+        """
+        return (
+            regex_obj["group_id"]
+            for regex_obj in self.namespaces[ApplicationService.NS_USERS]
+            if "group_id" in regex_obj and regex_obj["regex"].match(user_id)
+        )
+
     def is_rate_limited(self):
         return self.rate_limited
 
diff --git a/synapse/appservice/api.py b/synapse/appservice/api.py
index 6893610e71..40c433d7ae 100644
--- a/synapse/appservice/api.py
+++ b/synapse/appservice/api.py
@@ -18,6 +18,7 @@ from synapse.api.constants import ThirdPartyEntityKind
 from synapse.api.errors import CodeMessageException
 from synapse.http.client import SimpleHttpClient
 from synapse.events.utils import serialize_event
+from synapse.util.logcontext import preserve_fn, make_deferred_yieldable
 from synapse.util.caches.response_cache import ResponseCache
 from synapse.types import ThirdPartyInstanceID
 
@@ -192,9 +193,12 @@ class ApplicationServiceApi(SimpleHttpClient):
                 defer.returnValue(None)
 
         key = (service.id, protocol)
-        return self.protocol_meta_cache.get(key) or (
-            self.protocol_meta_cache.set(key, _get())
-        )
+        result = self.protocol_meta_cache.get(key)
+        if not result:
+            result = self.protocol_meta_cache.set(
+                key, preserve_fn(_get)()
+            )
+        return make_deferred_yieldable(result)
 
     @defer.inlineCallbacks
     def push_bulk(self, service, events, txn_id=None):
diff --git a/synapse/appservice/scheduler.py b/synapse/appservice/scheduler.py
index 68a9de17b8..6da315473d 100644
--- a/synapse/appservice/scheduler.py
+++ b/synapse/appservice/scheduler.py
@@ -123,7 +123,7 @@ class _ServiceQueuer(object):
                 with Measure(self.clock, "servicequeuer.send"):
                     try:
                         yield self.txn_ctrl.send(service, events)
-                    except:
+                    except Exception:
                         logger.exception("AS request failed")
         finally:
             self.requests_in_flight.discard(service.id)
diff --git a/synapse/config/_base.py b/synapse/config/_base.py
index 1ab5593c6e..fa105bce72 100644
--- a/synapse/config/_base.py
+++ b/synapse/config/_base.py
@@ -82,21 +82,37 @@ class Config(object):
         return os.path.abspath(file_path) if file_path else file_path
 
     @classmethod
+    def path_exists(cls, file_path):
+        """Check if a file exists
+
+        Unlike os.path.exists, this throws an exception if there is an error
+        checking if the file exists (for example, if there is a perms error on
+        the parent dir).
+
+        Returns:
+            bool: True if the file exists; False if not.
+        """
+        try:
+            os.stat(file_path)
+            return True
+        except OSError as e:
+            if e.errno != errno.ENOENT:
+                raise e
+            return False
+
+    @classmethod
     def check_file(cls, file_path, config_name):
         if file_path is None:
             raise ConfigError(
                 "Missing config for %s."
-                " You must specify a path for the config file. You can "
-                "do this with the -c or --config-path option. "
-                "Adding --generate-config along with --server-name "
-                "<server name> will generate a config file at the given path."
                 % (config_name,)
             )
-        if not os.path.exists(file_path):
+        try:
+            os.stat(file_path)
+        except OSError as e:
             raise ConfigError(
-                "File %s config for %s doesn't exist."
-                " Try running again with --generate-config"
-                % (file_path, config_name,)
+                "Error accessing file '%s' (config for %s): %s"
+                % (file_path, config_name, e.strerror)
             )
         return cls.abspath(file_path)
 
@@ -248,7 +264,7 @@ class Config(object):
                     " -c CONFIG-FILE\""
                 )
             (config_path,) = config_files
-            if not os.path.exists(config_path):
+            if not cls.path_exists(config_path):
                 if config_args.keys_directory:
                     config_dir_path = config_args.keys_directory
                 else:
@@ -261,7 +277,7 @@ class Config(object):
                         "Must specify a server_name to a generate config for."
                         " Pass -H server.name."
                     )
-                if not os.path.exists(config_dir_path):
+                if not cls.path_exists(config_dir_path):
                     os.makedirs(config_dir_path)
                 with open(config_path, "wb") as config_file:
                     config_bytes, config = obj.generate_config(
diff --git a/synapse/config/appservice.py b/synapse/config/appservice.py
index 82c50b8240..aba0aec6e8 100644
--- a/synapse/config/appservice.py
+++ b/synapse/config/appservice.py
@@ -154,6 +154,7 @@ def _load_appservice(hostname, as_info, config_filename):
         )
     return ApplicationService(
         token=as_info["as_token"],
+        hostname=hostname,
         url=as_info["url"],
         namespaces=as_info["namespaces"],
         hs_token=as_info["hs_token"],
diff --git a/synapse/config/cas.py b/synapse/config/cas.py
index 938f6f25f8..8109e5f95e 100644
--- a/synapse/config/cas.py
+++ b/synapse/config/cas.py
@@ -41,7 +41,7 @@ class CasConfig(Config):
         #cas_config:
         #   enabled: true
         #   server_url: "https://cas-server.com"
-        #   service_url: "https://homesever.domain.com:8448"
+        #   service_url: "https://homeserver.domain.com:8448"
         #   #required_attributes:
         #   #    name: value
         """
diff --git a/synapse/config/groups.py b/synapse/config/groups.py
new file mode 100644
index 0000000000..997fa2881f
--- /dev/null
+++ b/synapse/config/groups.py
@@ -0,0 +1,32 @@
+# -*- coding: utf-8 -*-
+# Copyright 2017 New Vector Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from ._base import Config
+
+
+class GroupsConfig(Config):
+    def read_config(self, config):
+        self.enable_group_creation = config.get("enable_group_creation", False)
+        self.group_creation_prefix = config.get("group_creation_prefix", "")
+
+    def default_config(self, **kwargs):
+        return """\
+        # Whether to allow non server admins to create groups on this server
+        enable_group_creation: false
+
+        # If enabled, non server admins can only create groups with local parts
+        # starting with this prefix
+        # group_creation_prefix: "unofficial/"
+        """
diff --git a/synapse/config/homeserver.py b/synapse/config/homeserver.py
index 3f9d9d5f8b..bf19cfee29 100644
--- a/synapse/config/homeserver.py
+++ b/synapse/config/homeserver.py
@@ -35,6 +35,8 @@ from .emailconfig import EmailConfig
 from .workers import WorkerConfig
 from .push import PushConfig
 from .spam_checker import SpamCheckerConfig
+from .groups import GroupsConfig
+from .user_directory import UserDirectoryConfig
 
 
 class HomeServerConfig(TlsConfig, ServerConfig, DatabaseConfig, LoggingConfig,
@@ -43,7 +45,7 @@ class HomeServerConfig(TlsConfig, ServerConfig, DatabaseConfig, LoggingConfig,
                        AppServiceConfig, KeyConfig, SAML2Config, CasConfig,
                        JWTConfig, PasswordConfig, EmailConfig,
                        WorkerConfig, PasswordAuthProviderConfig, PushConfig,
-                       SpamCheckerConfig,):
+                       SpamCheckerConfig, GroupsConfig, UserDirectoryConfig,):
     pass
 
 
diff --git a/synapse/config/key.py b/synapse/config/key.py
index 6ee643793e..4b8fc063d0 100644
--- a/synapse/config/key.py
+++ b/synapse/config/key.py
@@ -118,10 +118,9 @@ class KeyConfig(Config):
         signing_keys = self.read_file(signing_key_path, "signing_key")
         try:
             return read_signing_keys(signing_keys.splitlines(True))
-        except Exception:
+        except Exception as e:
             raise ConfigError(
-                "Error reading signing_key."
-                " Try running again with --generate-config"
+                "Error reading signing_key: %s" % (str(e))
             )
 
     def read_old_signing_keys(self, old_signing_keys):
@@ -141,7 +140,8 @@ class KeyConfig(Config):
 
     def generate_files(self, config):
         signing_key_path = config["signing_key_path"]
-        if not os.path.exists(signing_key_path):
+
+        if not self.path_exists(signing_key_path):
             with open(signing_key_path, "w") as signing_key_file:
                 key_id = "a_" + random_string(4)
                 write_signing_keys(
diff --git a/synapse/config/logger.py b/synapse/config/logger.py
index 2dbeafa9dd..a1d6e4d4f7 100644
--- a/synapse/config/logger.py
+++ b/synapse/config/logger.py
@@ -148,8 +148,8 @@ def setup_logging(config, use_worker_options=False):
         "%(asctime)s - %(name)s - %(lineno)d - %(levelname)s - %(request)s"
         " - %(message)s"
     )
-    if log_config is None:
 
+    if log_config is None:
         level = logging.INFO
         level_for_storage = logging.INFO
         if config.verbosity:
@@ -176,6 +176,10 @@ def setup_logging(config, use_worker_options=False):
                 logger.info("Opened new log file due to SIGHUP")
         else:
             handler = logging.StreamHandler()
+
+            def sighup(signum, stack):
+                pass
+
         handler.setFormatter(formatter)
 
         handler.addFilter(LoggingContextFilter(request=""))
diff --git a/synapse/config/password_auth_providers.py b/synapse/config/password_auth_providers.py
index 90824cab7f..e9828fac17 100644
--- a/synapse/config/password_auth_providers.py
+++ b/synapse/config/password_auth_providers.py
@@ -13,41 +13,40 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-from ._base import Config, ConfigError
+from ._base import Config
 
 from synapse.util.module_loader import load_module
 
+LDAP_PROVIDER = 'ldap_auth_provider.LdapAuthProvider'
+
 
 class PasswordAuthProviderConfig(Config):
     def read_config(self, config):
         self.password_providers = []
-
-        provider_config = None
+        providers = []
 
         # We want to be backwards compatible with the old `ldap_config`
         # param.
         ldap_config = config.get("ldap_config", {})
-        self.ldap_enabled = ldap_config.get("enabled", False)
-        if self.ldap_enabled:
-            from ldap_auth_provider import LdapAuthProvider
-            parsed_config = LdapAuthProvider.parse_config(ldap_config)
-            self.password_providers.append((LdapAuthProvider, parsed_config))
+        if ldap_config.get("enabled", False):
+            providers.append[{
+                'module': LDAP_PROVIDER,
+                'config': ldap_config,
+            }]
 
-        providers = config.get("password_providers", [])
+        providers.extend(config.get("password_providers", []))
         for provider in providers:
+            mod_name = provider['module']
+
             # This is for backwards compat when the ldap auth provider resided
             # in this package.
-            if provider['module'] == "synapse.util.ldap_auth_provider.LdapAuthProvider":
-                from ldap_auth_provider import LdapAuthProvider
-                provider_class = LdapAuthProvider
-                try:
-                    provider_config = provider_class.parse_config(provider["config"])
-                except Exception as e:
-                    raise ConfigError(
-                        "Failed to parse config for %r: %r" % (provider['module'], e)
-                    )
-            else:
-                (provider_class, provider_config) = load_module(provider)
+            if mod_name == "synapse.util.ldap_auth_provider.LdapAuthProvider":
+                mod_name = LDAP_PROVIDER
+
+            (provider_class, provider_config) = load_module({
+                "module": mod_name,
+                "config": provider['config'],
+            })
 
             self.password_providers.append((provider_class, provider_config))
 
diff --git a/synapse/config/push.py b/synapse/config/push.py
index 9c68318b40..b7e0d46afa 100644
--- a/synapse/config/push.py
+++ b/synapse/config/push.py
@@ -1,5 +1,6 @@
 # -*- coding: utf-8 -*-
 # Copyright 2015, 2016 OpenMarket Ltd
+# Copyright 2017 New Vector Ltd
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -18,28 +19,43 @@ from ._base import Config
 
 class PushConfig(Config):
     def read_config(self, config):
-        self.push_redact_content = False
+        push_config = config.get("push", {})
+        self.push_include_content = push_config.get("include_content", True)
 
+        # There was a a 'redact_content' setting but mistakenly read from the
+        # 'email'section'. Check for the flag in the 'push' section, and log,
+        # but do not honour it to avoid nasty surprises when people upgrade.
+        if push_config.get("redact_content") is not None:
+            print(
+                "The push.redact_content content option has never worked. "
+                "Please set push.include_content if you want this behaviour"
+            )
+
+        # Now check for the one in the 'email' section and honour it,
+        # with a warning.
         push_config = config.get("email", {})
-        self.push_redact_content = push_config.get("redact_content", False)
+        redact_content = push_config.get("redact_content")
+        if redact_content is not None:
+            print(
+                "The 'email.redact_content' option is deprecated: "
+                "please set push.include_content instead"
+            )
+            self.push_include_content = not redact_content
 
     def default_config(self, config_dir_path, server_name, **kwargs):
         return """
-        # Control how push messages are sent to google/apple to notifications.
-        # Normally every message said in a room with one or more people using
-        # mobile devices will be posted to a push server hosted by matrix.org
-        # which is registered with google and apple in order to allow push
-        # notifications to be sent to these mobile devices.
-        #
-        # Setting redact_content to true will make the push messages contain no
-        # message content which will provide increased privacy. This is a
-        # temporary solution pending improvements to Android and iPhone apps
-        # to get content from the app rather than the notification.
-        #
+        # Clients requesting push notifications can either have the body of
+        # the message sent in the notification poke along with other details
+        # like the sender, or just the event ID and room ID (`event_id_only`).
+        # If clients choose the former, this option controls whether the
+        # notification request includes the content of the event (other details
+        # like the sender are still included). For `event_id_only` push, it
+        # has no effect.
+
         # For modern android devices the notification content will still appear
         # because it is loaded by the app. iPhone, however will send a
         # notification saying only that a message arrived and who it came from.
         #
         #push:
-        #   redact_content: false
+        #   include_content: true
         """
diff --git a/synapse/config/registration.py b/synapse/config/registration.py
index f7e03c4cde..ef917fc9f2 100644
--- a/synapse/config/registration.py
+++ b/synapse/config/registration.py
@@ -41,6 +41,8 @@ class RegistrationConfig(Config):
             self.allow_guest_access and config.get("invite_3pid_guest", False)
         )
 
+        self.auto_join_rooms = config.get("auto_join_rooms", [])
+
     def default_config(self, **kwargs):
         registration_shared_secret = random_string_with_symbols(50)
 
@@ -70,6 +72,11 @@ class RegistrationConfig(Config):
             - matrix.org
             - vector.im
             - riot.im
+
+        # Users who register on this homeserver will automatically be joined
+        # to these rooms
+        #auto_join_rooms:
+        #    - "#example:example.com"
         """ % locals()
 
     def add_arguments(self, parser):
diff --git a/synapse/config/repository.py b/synapse/config/repository.py
index 2c6f57168e..6baa474931 100644
--- a/synapse/config/repository.py
+++ b/synapse/config/repository.py
@@ -70,7 +70,19 @@ class ContentRepositoryConfig(Config):
         self.max_upload_size = self.parse_size(config["max_upload_size"])
         self.max_image_pixels = self.parse_size(config["max_image_pixels"])
         self.max_spider_size = self.parse_size(config["max_spider_size"])
+
         self.media_store_path = self.ensure_directory(config["media_store_path"])
+
+        self.backup_media_store_path = config.get("backup_media_store_path")
+        if self.backup_media_store_path:
+            self.backup_media_store_path = self.ensure_directory(
+                self.backup_media_store_path
+            )
+
+        self.synchronous_backup_media_store = config.get(
+            "synchronous_backup_media_store", False
+        )
+
         self.uploads_path = self.ensure_directory(config["uploads_path"])
         self.dynamic_thumbnails = config["dynamic_thumbnails"]
         self.thumbnail_requirements = parse_thumbnail_requirements(
@@ -115,6 +127,14 @@ class ContentRepositoryConfig(Config):
         # Directory where uploaded images and attachments are stored.
         media_store_path: "%(media_store)s"
 
+        # A secondary directory where uploaded images and attachments are
+        # stored as a backup.
+        # backup_media_store_path: "%(media_store)s"
+
+        # Whether to wait for successful write to backup media store before
+        # returning successfully.
+        # synchronous_backup_media_store: false
+
         # Directory where in-progress uploads are stored.
         uploads_path: "%(uploads_path)s"
 
diff --git a/synapse/config/server.py b/synapse/config/server.py
index c9a1715f1f..edb90a1348 100644
--- a/synapse/config/server.py
+++ b/synapse/config/server.py
@@ -41,6 +41,12 @@ class ServerConfig(Config):
         # false only if we are updating the user directory in a worker
         self.update_user_directory = config.get("update_user_directory", True)
 
+        # whether to enable the media repository endpoints. This should be set
+        # to false if the media repository is running as a separate endpoint;
+        # doing so ensures that we will not run cache cleanup jobs on the
+        # master, potentially causing inconsistency.
+        self.enable_media_repo = config.get("enable_media_repo", True)
+
         self.filter_timeline_limit = config.get("filter_timeline_limit", -1)
 
         # Whether we should block invites sent to users on this server
@@ -247,6 +253,13 @@ class ServerConfig(Config):
               - names: [federation]  # Federation APIs
                 compress: false
 
+            # optional list of additional endpoints which can be loaded via
+            # dynamic modules
+            # additional_resources:
+            #   "/_matrix/my/custom/endpoint":
+            #     module: my_module.CustomRequestHandler
+            #     config: {}
+
           # Unsecure HTTP listener,
           # For when matrix traffic passes through loadbalancer that unwraps TLS.
           - port: %(unsecure_port)s
@@ -303,7 +316,7 @@ def read_gc_thresholds(thresholds):
         return (
             int(thresholds[0]), int(thresholds[1]), int(thresholds[2]),
         )
-    except:
+    except Exception:
         raise ConfigError(
             "Value of `gc_threshold` must be a list of three integers if set"
         )
diff --git a/synapse/config/tls.py b/synapse/config/tls.py
index e081840a83..4748f71c2f 100644
--- a/synapse/config/tls.py
+++ b/synapse/config/tls.py
@@ -109,6 +109,12 @@ class TlsConfig(Config):
         # key. It may be necessary to publish the fingerprints of a new
         # certificate and wait until the "valid_until_ts" of the previous key
         # responses have passed before deploying it.
+        #
+        # You can calculate a fingerprint from a given TLS listener via:
+        # openssl s_client -connect $host:$port < /dev/null 2> /dev/null |
+        #   openssl x509 -outform DER | openssl sha256 -binary | base64 | tr -d '='
+        # or by checking matrix.org/federationtester/api/report?server_name=$host
+        #
         tls_fingerprints: []
         # tls_fingerprints: [{"sha256": "<base64_encoded_sha256_fingerprint>"}]
         """ % locals()
@@ -126,7 +132,7 @@ class TlsConfig(Config):
         tls_private_key_path = config["tls_private_key_path"]
         tls_dh_params_path = config["tls_dh_params_path"]
 
-        if not os.path.exists(tls_private_key_path):
+        if not self.path_exists(tls_private_key_path):
             with open(tls_private_key_path, "w") as private_key_file:
                 tls_private_key = crypto.PKey()
                 tls_private_key.generate_key(crypto.TYPE_RSA, 2048)
@@ -141,7 +147,7 @@ class TlsConfig(Config):
                     crypto.FILETYPE_PEM, private_key_pem
                 )
 
-        if not os.path.exists(tls_certificate_path):
+        if not self.path_exists(tls_certificate_path):
             with open(tls_certificate_path, "w") as certificate_file:
                 cert = crypto.X509()
                 subject = cert.get_subject()
@@ -159,7 +165,7 @@ class TlsConfig(Config):
 
                 certificate_file.write(cert_pem)
 
-        if not os.path.exists(tls_dh_params_path):
+        if not self.path_exists(tls_dh_params_path):
             if GENERATE_DH_PARAMS:
                 subprocess.check_call([
                     "openssl", "dhparam",
diff --git a/synapse/config/user_directory.py b/synapse/config/user_directory.py
new file mode 100644
index 0000000000..38e8947843
--- /dev/null
+++ b/synapse/config/user_directory.py
@@ -0,0 +1,44 @@
+# -*- coding: utf-8 -*-
+# Copyright 2017 New Vector Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from ._base import Config
+
+
+class UserDirectoryConfig(Config):
+    """User Directory Configuration
+    Configuration for the behaviour of the /user_directory API
+    """
+
+    def read_config(self, config):
+        self.user_directory_search_all_users = False
+        user_directory_config = config.get("user_directory", None)
+        if user_directory_config:
+            self.user_directory_search_all_users = (
+                user_directory_config.get("search_all_users", False)
+            )
+
+    def default_config(self, config_dir_path, server_name, **kwargs):
+        return """
+        # User Directory configuration
+        #
+        # 'search_all_users' defines whether to search all users visible to your HS
+        # when searching the user directory, rather than limiting to users visible
+        # in public rooms.  Defaults to false.  If you set it True, you'll have to run
+        # UPDATE user_directory_stream_pos SET stream_id = NULL;
+        # on your database to tell it to rebuild the user_directory search indexes.
+        #
+        #user_directory:
+        #   search_all_users: false
+        """
diff --git a/synapse/crypto/context_factory.py b/synapse/crypto/context_factory.py
index aad4752fe7..cff3ca809a 100644
--- a/synapse/crypto/context_factory.py
+++ b/synapse/crypto/context_factory.py
@@ -34,7 +34,7 @@ class ServerContextFactory(ssl.ContextFactory):
         try:
             _ecCurve = _OpenSSLECCurve(_defaultCurveName)
             _ecCurve.addECKeyToContext(context)
-        except:
+        except Exception:
             logger.exception("Failed to enable elliptic curve for TLS")
         context.set_options(SSL.OP_NO_SSLv2 | SSL.OP_NO_SSLv3)
         context.use_certificate_chain_file(config.tls_certificate_file)
diff --git a/synapse/crypto/event_signing.py b/synapse/crypto/event_signing.py
index ec7711ba7d..aaa3efaca3 100644
--- a/synapse/crypto/event_signing.py
+++ b/synapse/crypto/event_signing.py
@@ -32,18 +32,25 @@ def check_event_content_hash(event, hash_algorithm=hashlib.sha256):
     """Check whether the hash for this PDU matches the contents"""
     name, expected_hash = compute_content_hash(event, hash_algorithm)
     logger.debug("Expecting hash: %s", encode_base64(expected_hash))
-    if name not in event.hashes:
+
+    # some malformed events lack a 'hashes'. Protect against it being missing
+    # or a weird type by basically treating it the same as an unhashed event.
+    hashes = event.get("hashes")
+    if not isinstance(hashes, dict):
+        raise SynapseError(400, "Malformed 'hashes'", Codes.UNAUTHORIZED)
+
+    if name not in hashes:
         raise SynapseError(
             400,
             "Algorithm %s not in hashes %s" % (
-                name, list(event.hashes),
+                name, list(hashes),
             ),
             Codes.UNAUTHORIZED,
         )
-    message_hash_base64 = event.hashes[name]
+    message_hash_base64 = hashes[name]
     try:
         message_hash_bytes = decode_base64(message_hash_base64)
-    except:
+    except Exception:
         raise SynapseError(
             400,
             "Invalid base64: %s" % (message_hash_base64,),
diff --git a/synapse/crypto/keyring.py b/synapse/crypto/keyring.py
index 054bac456d..35f810b07b 100644
--- a/synapse/crypto/keyring.py
+++ b/synapse/crypto/keyring.py
@@ -759,7 +759,7 @@ def _handle_key_deferred(verify_request):
     ))
     try:
         verify_signed_json(json_object, server_name, verify_key)
-    except:
+    except Exception:
         raise SynapseError(
             401,
             "Invalid signature for server %s with key %s:%s" % (
diff --git a/synapse/event_auth.py b/synapse/event_auth.py
index 4096c606f1..061ee86b16 100644
--- a/synapse/event_auth.py
+++ b/synapse/event_auth.py
@@ -443,12 +443,12 @@ def _check_power_levels(event, auth_events):
     for k, v in user_list.items():
         try:
             UserID.from_string(k)
-        except:
+        except Exception:
             raise SynapseError(400, "Not a valid user_id: %s" % (k,))
 
         try:
             int(v)
-        except:
+        except Exception:
             raise SynapseError(400, "Not a valid power level: %s" % (v,))
 
     key = (event.type, event.state_key, )
@@ -470,14 +470,14 @@ def _check_power_levels(event, auth_events):
         ("invite", None),
     ]
 
-    old_list = current_state.content.get("users")
+    old_list = current_state.content.get("users", {})
     for user in set(old_list.keys() + user_list.keys()):
         levels_to_check.append(
             (user, "users")
         )
 
-    old_list = current_state.content.get("events")
-    new_list = event.content.get("events")
+    old_list = current_state.content.get("events", {})
+    new_list = event.content.get("events", {})
     for ev_id in set(old_list.keys() + new_list.keys()):
         levels_to_check.append(
             (ev_id, "events")
diff --git a/synapse/events/builder.py b/synapse/events/builder.py
index 365fd96bd2..13fbba68c0 100644
--- a/synapse/events/builder.py
+++ b/synapse/events/builder.py
@@ -55,7 +55,7 @@ class EventBuilderFactory(object):
 
         local_part = str(int(self.clock.time())) + i + random_string(5)
 
-        e_id = EventID.create(local_part, self.hostname)
+        e_id = EventID(local_part, self.hostname)
 
         return e_id.to_string()
 
diff --git a/synapse/events/spamcheck.py b/synapse/events/spamcheck.py
index e739f105b2..633e068eb8 100644
--- a/synapse/events/spamcheck.py
+++ b/synapse/events/spamcheck.py
@@ -22,7 +22,7 @@ class SpamChecker(object):
         config = None
         try:
             module, config = hs.config.spam_checker
-        except:
+        except Exception:
             pass
 
         if module is not None:
@@ -45,3 +45,69 @@ class SpamChecker(object):
             return False
 
         return self.spam_checker.check_event_for_spam(event)
+
+    def user_may_invite(self, inviter_userid, invitee_userid, room_id):
+        """Checks if a given user may send an invite
+
+        If this method returns false, the invite will be rejected.
+
+        Args:
+            userid (string): The sender's user ID
+
+        Returns:
+            bool: True if the user may send an invite, otherwise False
+        """
+        if self.spam_checker is None:
+            return True
+
+        return self.spam_checker.user_may_invite(inviter_userid, invitee_userid, room_id)
+
+    def user_may_create_room(self, userid):
+        """Checks if a given user may create a room
+
+        If this method returns false, the creation request will be rejected.
+
+        Args:
+            userid (string): The sender's user ID
+
+        Returns:
+            bool: True if the user may create a room, otherwise False
+        """
+        if self.spam_checker is None:
+            return True
+
+        return self.spam_checker.user_may_create_room(userid)
+
+    def user_may_create_room_alias(self, userid, room_alias):
+        """Checks if a given user may create a room alias
+
+        If this method returns false, the association request will be rejected.
+
+        Args:
+            userid (string): The sender's user ID
+            room_alias (string): The alias to be created
+
+        Returns:
+            bool: True if the user may create a room alias, otherwise False
+        """
+        if self.spam_checker is None:
+            return True
+
+        return self.spam_checker.user_may_create_room_alias(userid, room_alias)
+
+    def user_may_publish_room(self, userid, room_id):
+        """Checks if a given user may publish a room to the directory
+
+        If this method returns false, the publish request will be rejected.
+
+        Args:
+            userid (string): The sender's user ID
+            room_id (string): The ID of the room that would be published
+
+        Returns:
+            bool: True if the user may publish the room, otherwise False
+        """
+        if self.spam_checker is None:
+            return True
+
+        return self.spam_checker.user_may_publish_room(userid, room_id)
diff --git a/synapse/federation/federation_client.py b/synapse/federation/federation_client.py
index 7c5e5d957f..b8f02f5391 100644
--- a/synapse/federation/federation_client.py
+++ b/synapse/federation/federation_client.py
@@ -25,7 +25,7 @@ from synapse.api.errors import (
 from synapse.util import unwrapFirstError, logcontext
 from synapse.util.caches.expiringcache import ExpiringCache
 from synapse.util.logutils import log_function
-from synapse.util.logcontext import preserve_fn, preserve_context_over_deferred
+from synapse.util.logcontext import make_deferred_yieldable, preserve_fn
 from synapse.events import FrozenEvent, builder
 import synapse.metrics
 
@@ -420,7 +420,7 @@ class FederationClient(FederationBase):
                 for e_id in batch
             ]
 
-            res = yield preserve_context_over_deferred(
+            res = yield make_deferred_yieldable(
                 defer.DeferredList(deferreds, consumeErrors=True)
             )
             for success, result in res:
diff --git a/synapse/federation/federation_server.py b/synapse/federation/federation_server.py
index 51e3fdea06..a2327f24b6 100644
--- a/synapse/federation/federation_server.py
+++ b/synapse/federation/federation_server.py
@@ -12,14 +12,13 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-
-
 from twisted.internet import defer
 
 from .federation_base import FederationBase
 from .units import Transaction, Edu
 
-from synapse.util.async import Linearizer
+from synapse.util import async
+from synapse.util.logcontext import make_deferred_yieldable, preserve_fn
 from synapse.util.logutils import log_function
 from synapse.util.caches.response_cache import ResponseCache
 from synapse.events import FrozenEvent
@@ -33,6 +32,9 @@ from synapse.crypto.event_signing import compute_event_signature
 import simplejson as json
 import logging
 
+# when processing incoming transactions, we try to handle multiple rooms in
+# parallel, up to this limit.
+TRANSACTION_CONCURRENCY_LIMIT = 10
 
 logger = logging.getLogger(__name__)
 
@@ -52,7 +54,8 @@ class FederationServer(FederationBase):
 
         self.auth = hs.get_auth()
 
-        self._server_linearizer = Linearizer("fed_server")
+        self._server_linearizer = async.Linearizer("fed_server")
+        self._transaction_linearizer = async.Linearizer("fed_txn_handler")
 
         # We cache responses to state queries, as they take a while and often
         # come in waves.
@@ -109,25 +112,41 @@ class FederationServer(FederationBase):
     @defer.inlineCallbacks
     @log_function
     def on_incoming_transaction(self, transaction_data):
+        # keep this as early as possible to make the calculated origin ts as
+        # accurate as possible.
+        request_time = self._clock.time_msec()
+
         transaction = Transaction(**transaction_data)
 
-        received_pdus_counter.inc_by(len(transaction.pdus))
+        if not transaction.transaction_id:
+            raise Exception("Transaction missing transaction_id")
+        if not transaction.origin:
+            raise Exception("Transaction missing origin")
 
-        for p in transaction.pdus:
-            if "unsigned" in p:
-                unsigned = p["unsigned"]
-                if "age" in unsigned:
-                    p["age"] = unsigned["age"]
-            if "age" in p:
-                p["age_ts"] = int(self._clock.time_msec()) - int(p["age"])
-                del p["age"]
+        logger.debug("[%s] Got transaction", transaction.transaction_id)
 
-        pdu_list = [
-            self.event_from_pdu_json(p) for p in transaction.pdus
-        ]
+        # use a linearizer to ensure that we don't process the same transaction
+        # multiple times in parallel.
+        with (yield self._transaction_linearizer.queue(
+                (transaction.origin, transaction.transaction_id),
+        )):
+            result = yield self._handle_incoming_transaction(
+                transaction, request_time,
+            )
 
-        logger.debug("[%s] Got transaction", transaction.transaction_id)
+        defer.returnValue(result)
+
+    @defer.inlineCallbacks
+    def _handle_incoming_transaction(self, transaction, request_time):
+        """ Process an incoming transaction and return the HTTP response
+
+        Args:
+            transaction (Transaction): incoming transaction
+            request_time (int): timestamp that the HTTP request arrived at
 
+        Returns:
+            Deferred[(int, object)]: http response code and body
+        """
         response = yield self.transaction_actions.have_responded(transaction)
 
         if response:
@@ -140,42 +159,49 @@ class FederationServer(FederationBase):
 
         logger.debug("[%s] Transaction is new", transaction.transaction_id)
 
-        results = []
-
-        for pdu in pdu_list:
-            # check that it's actually being sent from a valid destination to
-            # workaround bug #1753 in 0.18.5 and 0.18.6
-            if transaction.origin != get_domain_from_id(pdu.event_id):
-                # We continue to accept join events from any server; this is
-                # necessary for the federation join dance to work correctly.
-                # (When we join over federation, the "helper" server is
-                # responsible for sending out the join event, rather than the
-                # origin. See bug #1893).
-                if not (
-                    pdu.type == 'm.room.member' and
-                    pdu.content and
-                    pdu.content.get("membership", None) == 'join'
-                ):
-                    logger.info(
-                        "Discarding PDU %s from invalid origin %s",
-                        pdu.event_id, transaction.origin
-                    )
-                    continue
-                else:
-                    logger.info(
-                        "Accepting join PDU %s from %s",
-                        pdu.event_id, transaction.origin
-                    )
+        received_pdus_counter.inc_by(len(transaction.pdus))
 
-            try:
-                yield self._handle_received_pdu(transaction.origin, pdu)
-                results.append({})
-            except FederationError as e:
-                self.send_failure(e, transaction.origin)
-                results.append({"error": str(e)})
-            except Exception as e:
-                results.append({"error": str(e)})
-                logger.exception("Failed to handle PDU")
+        pdus_by_room = {}
+
+        for p in transaction.pdus:
+            if "unsigned" in p:
+                unsigned = p["unsigned"]
+                if "age" in unsigned:
+                    p["age"] = unsigned["age"]
+            if "age" in p:
+                p["age_ts"] = request_time - int(p["age"])
+                del p["age"]
+
+            event = self.event_from_pdu_json(p)
+            room_id = event.room_id
+            pdus_by_room.setdefault(room_id, []).append(event)
+
+        pdu_results = {}
+
+        # we can process different rooms in parallel (which is useful if they
+        # require callouts to other servers to fetch missing events), but
+        # impose a limit to avoid going too crazy with ram/cpu.
+        @defer.inlineCallbacks
+        def process_pdus_for_room(room_id):
+            logger.debug("Processing PDUs for %s", room_id)
+            for pdu in pdus_by_room[room_id]:
+                event_id = pdu.event_id
+                try:
+                    yield self._handle_received_pdu(
+                        transaction.origin, pdu
+                    )
+                    pdu_results[event_id] = {}
+                except FederationError as e:
+                    logger.warn("Error handling PDU %s: %s", event_id, e)
+                    pdu_results[event_id] = {"error": str(e)}
+                except Exception as e:
+                    pdu_results[event_id] = {"error": str(e)}
+                    logger.exception("Failed to handle PDU %s", event_id)
+
+        yield async.concurrently_execute(
+            process_pdus_for_room, pdus_by_room.keys(),
+            TRANSACTION_CONCURRENCY_LIMIT,
+        )
 
         if hasattr(transaction, "edus"):
             for edu in (Edu(**x) for x in transaction.edus):
@@ -185,17 +211,16 @@ class FederationServer(FederationBase):
                     edu.content
                 )
 
-            for failure in getattr(transaction, "pdu_failures", []):
-                logger.info("Got failure %r", failure)
-
-        logger.debug("Returning: %s", str(results))
+        pdu_failures = getattr(transaction, "pdu_failures", [])
+        for failure in pdu_failures:
+            logger.info("Got failure %r", failure)
 
         response = {
-            "pdus": dict(zip(
-                (p.event_id for p in pdu_list), results
-            )),
+            "pdus": pdu_results,
         }
 
+        logger.debug("Returning: %s", str(response))
+
         yield self.transaction_actions.set_response(
             transaction,
             200, response
@@ -229,12 +254,13 @@ class FederationServer(FederationBase):
         result = self._state_resp_cache.get((room_id, event_id))
         if not result:
             with (yield self._server_linearizer.queue((origin, room_id))):
-                resp = yield self._state_resp_cache.set(
+                d = self._state_resp_cache.set(
                     (room_id, event_id),
-                    self._on_context_state_request_compute(room_id, event_id)
+                    preserve_fn(self._on_context_state_request_compute)(room_id, event_id)
                 )
+                resp = yield make_deferred_yieldable(d)
         else:
-            resp = yield result
+            resp = yield make_deferred_yieldable(result)
 
         defer.returnValue((200, resp))
 
@@ -520,6 +546,30 @@ class FederationServer(FederationBase):
         Returns (Deferred): completes with None
         Raises: FederationError if the signatures / hash do not match
     """
+        # check that it's actually being sent from a valid destination to
+        # workaround bug #1753 in 0.18.5 and 0.18.6
+        if origin != get_domain_from_id(pdu.event_id):
+            # We continue to accept join events from any server; this is
+            # necessary for the federation join dance to work correctly.
+            # (When we join over federation, the "helper" server is
+            # responsible for sending out the join event, rather than the
+            # origin. See bug #1893).
+            if not (
+                pdu.type == 'm.room.member' and
+                pdu.content and
+                pdu.content.get("membership", None) == 'join'
+            ):
+                logger.info(
+                    "Discarding PDU %s from invalid origin %s",
+                    pdu.event_id, origin
+                )
+                return
+            else:
+                logger.info(
+                    "Accepting join PDU %s from %s",
+                    pdu.event_id, origin
+                )
+
         # Check signature.
         try:
             pdu = yield self._check_sigs_and_hash(pdu)
diff --git a/synapse/federation/transaction_queue.py b/synapse/federation/transaction_queue.py
index 003eaba893..3e7809b04f 100644
--- a/synapse/federation/transaction_queue.py
+++ b/synapse/federation/transaction_queue.py
@@ -20,8 +20,8 @@ from .persistence import TransactionActions
 from .units import Transaction, Edu
 
 from synapse.api.errors import HttpResponseException
+from synapse.util import logcontext, PreserveLoggingContext
 from synapse.util.async import run_on_reactor
-from synapse.util.logcontext import preserve_context_over_fn, preserve_fn
 from synapse.util.retryutils import NotRetryingDestination, get_retry_limiter
 from synapse.util.metrics import measure_func
 from synapse.handlers.presence import format_user_presence_state, get_interested_remotes
@@ -146,7 +146,6 @@ class TransactionQueue(object):
         else:
             return not destination.startswith("localhost")
 
-    @defer.inlineCallbacks
     def notify_new_events(self, current_id):
         """This gets called when we have some new events we might want to
         send out to other servers.
@@ -156,6 +155,13 @@ class TransactionQueue(object):
         if self._is_processing:
             return
 
+        # fire off a processing loop in the background. It's likely it will
+        # outlast the current request, so run it in the sentinel logcontext.
+        with PreserveLoggingContext():
+            self._process_event_queue_loop()
+
+    @defer.inlineCallbacks
+    def _process_event_queue_loop(self):
         try:
             self._is_processing = True
             while True:
@@ -231,11 +237,9 @@ class TransactionQueue(object):
                 (pdu, order)
             )
 
-            preserve_context_over_fn(
-                self._attempt_new_transaction, destination
-            )
+            self._attempt_new_transaction(destination)
 
-    @preserve_fn  # the caller should not yield on this
+    @logcontext.preserve_fn  # the caller should not yield on this
     @defer.inlineCallbacks
     def send_presence(self, states):
         """Send the new presence states to the appropriate destinations.
@@ -299,7 +303,7 @@ class TransactionQueue(object):
                     state.user_id: state for state in states
                 })
 
-                preserve_fn(self._attempt_new_transaction)(destination)
+                self._attempt_new_transaction(destination)
 
     def send_edu(self, destination, edu_type, content, key=None):
         edu = Edu(
@@ -321,9 +325,7 @@ class TransactionQueue(object):
         else:
             self.pending_edus_by_dest.setdefault(destination, []).append(edu)
 
-        preserve_context_over_fn(
-            self._attempt_new_transaction, destination
-        )
+        self._attempt_new_transaction(destination)
 
     def send_failure(self, failure, destination):
         if destination == self.server_name or destination == "localhost":
@@ -336,9 +338,7 @@ class TransactionQueue(object):
             destination, []
         ).append(failure)
 
-        preserve_context_over_fn(
-            self._attempt_new_transaction, destination
-        )
+        self._attempt_new_transaction(destination)
 
     def send_device_messages(self, destination):
         if destination == self.server_name or destination == "localhost":
@@ -347,15 +347,24 @@ class TransactionQueue(object):
         if not self.can_send_to(destination):
             return
 
-        preserve_context_over_fn(
-            self._attempt_new_transaction, destination
-        )
+        self._attempt_new_transaction(destination)
 
     def get_current_token(self):
         return 0
 
-    @defer.inlineCallbacks
     def _attempt_new_transaction(self, destination):
+        """Try to start a new transaction to this destination
+
+        If there is already a transaction in progress to this destination,
+        returns immediately. Otherwise kicks off the process of sending a
+        transaction in the background.
+
+        Args:
+            destination (str):
+
+        Returns:
+            None
+        """
         # list of (pending_pdu, deferred, order)
         if destination in self.pending_transactions:
             # XXX: pending_transactions can get stuck on by a never-ending
@@ -368,6 +377,19 @@ class TransactionQueue(object):
             )
             return
 
+        logger.debug("TX [%s] Starting transaction loop", destination)
+
+        # Drop the logcontext before starting the transaction. It doesn't
+        # really make sense to log all the outbound transactions against
+        # whatever path led us to this point: that's pretty arbitrary really.
+        #
+        # (this also means we can fire off _perform_transaction without
+        # yielding)
+        with logcontext.PreserveLoggingContext():
+            self._transaction_transmission_loop(destination)
+
+    @defer.inlineCallbacks
+    def _transaction_transmission_loop(self, destination):
         pending_pdus = []
         try:
             self.pending_transactions[destination] = 1
diff --git a/synapse/federation/transport/client.py b/synapse/federation/transport/client.py
index 52b2a717d2..1f3ce238f6 100644
--- a/synapse/federation/transport/client.py
+++ b/synapse/federation/transport/client.py
@@ -471,3 +471,418 @@ class TransportLayerClient(object):
         )
 
         defer.returnValue(content)
+
+    @log_function
+    def get_group_profile(self, destination, group_id, requester_user_id):
+        """Get a group profile
+        """
+        path = PREFIX + "/groups/%s/profile" % (group_id,)
+
+        return self.client.get_json(
+            destination=destination,
+            path=path,
+            args={"requester_user_id": requester_user_id},
+            ignore_backoff=True,
+        )
+
+    @log_function
+    def update_group_profile(self, destination, group_id, requester_user_id, content):
+        """Update a remote group profile
+
+        Args:
+            destination (str)
+            group_id (str)
+            requester_user_id (str)
+            content (dict): The new profile of the group
+        """
+        path = PREFIX + "/groups/%s/profile" % (group_id,)
+
+        return self.client.post_json(
+            destination=destination,
+            path=path,
+            args={"requester_user_id": requester_user_id},
+            data=content,
+            ignore_backoff=True,
+        )
+
+    @log_function
+    def get_group_summary(self, destination, group_id, requester_user_id):
+        """Get a group summary
+        """
+        path = PREFIX + "/groups/%s/summary" % (group_id,)
+
+        return self.client.get_json(
+            destination=destination,
+            path=path,
+            args={"requester_user_id": requester_user_id},
+            ignore_backoff=True,
+        )
+
+    @log_function
+    def get_rooms_in_group(self, destination, group_id, requester_user_id):
+        """Get all rooms in a group
+        """
+        path = PREFIX + "/groups/%s/rooms" % (group_id,)
+
+        return self.client.get_json(
+            destination=destination,
+            path=path,
+            args={"requester_user_id": requester_user_id},
+            ignore_backoff=True,
+        )
+
+    def add_room_to_group(self, destination, group_id, requester_user_id, room_id,
+                          content):
+        """Add a room to a group
+        """
+        path = PREFIX + "/groups/%s/room/%s" % (group_id, room_id,)
+
+        return self.client.post_json(
+            destination=destination,
+            path=path,
+            args={"requester_user_id": requester_user_id},
+            data=content,
+            ignore_backoff=True,
+        )
+
+    def update_room_in_group(self, destination, group_id, requester_user_id, room_id,
+                             config_key, content):
+        """Update room in group
+        """
+        path = PREFIX + "/groups/%s/room/%s/config/%s" % (group_id, room_id, config_key,)
+
+        return self.client.post_json(
+            destination=destination,
+            path=path,
+            args={"requester_user_id": requester_user_id},
+            data=content,
+            ignore_backoff=True,
+        )
+
+    def remove_room_from_group(self, destination, group_id, requester_user_id, room_id):
+        """Remove a room from a group
+        """
+        path = PREFIX + "/groups/%s/room/%s" % (group_id, room_id,)
+
+        return self.client.delete_json(
+            destination=destination,
+            path=path,
+            args={"requester_user_id": requester_user_id},
+            ignore_backoff=True,
+        )
+
+    @log_function
+    def get_users_in_group(self, destination, group_id, requester_user_id):
+        """Get users in a group
+        """
+        path = PREFIX + "/groups/%s/users" % (group_id,)
+
+        return self.client.get_json(
+            destination=destination,
+            path=path,
+            args={"requester_user_id": requester_user_id},
+            ignore_backoff=True,
+        )
+
+    @log_function
+    def get_invited_users_in_group(self, destination, group_id, requester_user_id):
+        """Get users that have been invited to a group
+        """
+        path = PREFIX + "/groups/%s/invited_users" % (group_id,)
+
+        return self.client.get_json(
+            destination=destination,
+            path=path,
+            args={"requester_user_id": requester_user_id},
+            ignore_backoff=True,
+        )
+
+    @log_function
+    def accept_group_invite(self, destination, group_id, user_id, content):
+        """Accept a group invite
+        """
+        path = PREFIX + "/groups/%s/users/%s/accept_invite" % (group_id, user_id)
+
+        return self.client.post_json(
+            destination=destination,
+            path=path,
+            data=content,
+            ignore_backoff=True,
+        )
+
+    @log_function
+    def invite_to_group(self, destination, group_id, user_id, requester_user_id, content):
+        """Invite a user to a group
+        """
+        path = PREFIX + "/groups/%s/users/%s/invite" % (group_id, user_id)
+
+        return self.client.post_json(
+            destination=destination,
+            path=path,
+            args={"requester_user_id": requester_user_id},
+            data=content,
+            ignore_backoff=True,
+        )
+
+    @log_function
+    def invite_to_group_notification(self, destination, group_id, user_id, content):
+        """Sent by group server to inform a user's server that they have been
+        invited.
+        """
+
+        path = PREFIX + "/groups/local/%s/users/%s/invite" % (group_id, user_id)
+
+        return self.client.post_json(
+            destination=destination,
+            path=path,
+            data=content,
+            ignore_backoff=True,
+        )
+
+    @log_function
+    def remove_user_from_group(self, destination, group_id, requester_user_id,
+                               user_id, content):
+        """Remove a user fron a group
+        """
+        path = PREFIX + "/groups/%s/users/%s/remove" % (group_id, user_id)
+
+        return self.client.post_json(
+            destination=destination,
+            path=path,
+            args={"requester_user_id": requester_user_id},
+            data=content,
+            ignore_backoff=True,
+        )
+
+    @log_function
+    def remove_user_from_group_notification(self, destination, group_id, user_id,
+                                            content):
+        """Sent by group server to inform a user's server that they have been
+        kicked from the group.
+        """
+
+        path = PREFIX + "/groups/local/%s/users/%s/remove" % (group_id, user_id)
+
+        return self.client.post_json(
+            destination=destination,
+            path=path,
+            data=content,
+            ignore_backoff=True,
+        )
+
+    @log_function
+    def renew_group_attestation(self, destination, group_id, user_id, content):
+        """Sent by either a group server or a user's server to periodically update
+        the attestations
+        """
+
+        path = PREFIX + "/groups/%s/renew_attestation/%s" % (group_id, user_id)
+
+        return self.client.post_json(
+            destination=destination,
+            path=path,
+            data=content,
+            ignore_backoff=True,
+        )
+
+    @log_function
+    def update_group_summary_room(self, destination, group_id, user_id, room_id,
+                                  category_id, content):
+        """Update a room entry in a group summary
+        """
+        if category_id:
+            path = PREFIX + "/groups/%s/summary/categories/%s/rooms/%s" % (
+                group_id, category_id, room_id,
+            )
+        else:
+            path = PREFIX + "/groups/%s/summary/rooms/%s" % (group_id, room_id,)
+
+        return self.client.post_json(
+            destination=destination,
+            path=path,
+            args={"requester_user_id": user_id},
+            data=content,
+            ignore_backoff=True,
+        )
+
+    @log_function
+    def delete_group_summary_room(self, destination, group_id, user_id, room_id,
+                                  category_id):
+        """Delete a room entry in a group summary
+        """
+        if category_id:
+            path = PREFIX + "/groups/%s/summary/categories/%s/rooms/%s" % (
+                group_id, category_id, room_id,
+            )
+        else:
+            path = PREFIX + "/groups/%s/summary/rooms/%s" % (group_id, room_id,)
+
+        return self.client.delete_json(
+            destination=destination,
+            path=path,
+            args={"requester_user_id": user_id},
+            ignore_backoff=True,
+        )
+
+    @log_function
+    def get_group_categories(self, destination, group_id, requester_user_id):
+        """Get all categories in a group
+        """
+        path = PREFIX + "/groups/%s/categories" % (group_id,)
+
+        return self.client.get_json(
+            destination=destination,
+            path=path,
+            args={"requester_user_id": requester_user_id},
+            ignore_backoff=True,
+        )
+
+    @log_function
+    def get_group_category(self, destination, group_id, requester_user_id, category_id):
+        """Get category info in a group
+        """
+        path = PREFIX + "/groups/%s/categories/%s" % (group_id, category_id,)
+
+        return self.client.get_json(
+            destination=destination,
+            path=path,
+            args={"requester_user_id": requester_user_id},
+            ignore_backoff=True,
+        )
+
+    @log_function
+    def update_group_category(self, destination, group_id, requester_user_id, category_id,
+                              content):
+        """Update a category in a group
+        """
+        path = PREFIX + "/groups/%s/categories/%s" % (group_id, category_id,)
+
+        return self.client.post_json(
+            destination=destination,
+            path=path,
+            args={"requester_user_id": requester_user_id},
+            data=content,
+            ignore_backoff=True,
+        )
+
+    @log_function
+    def delete_group_category(self, destination, group_id, requester_user_id,
+                              category_id):
+        """Delete a category in a group
+        """
+        path = PREFIX + "/groups/%s/categories/%s" % (group_id, category_id,)
+
+        return self.client.delete_json(
+            destination=destination,
+            path=path,
+            args={"requester_user_id": requester_user_id},
+            ignore_backoff=True,
+        )
+
+    @log_function
+    def get_group_roles(self, destination, group_id, requester_user_id):
+        """Get all roles in a group
+        """
+        path = PREFIX + "/groups/%s/roles" % (group_id,)
+
+        return self.client.get_json(
+            destination=destination,
+            path=path,
+            args={"requester_user_id": requester_user_id},
+            ignore_backoff=True,
+        )
+
+    @log_function
+    def get_group_role(self, destination, group_id, requester_user_id, role_id):
+        """Get a roles info
+        """
+        path = PREFIX + "/groups/%s/roles/%s" % (group_id, role_id,)
+
+        return self.client.get_json(
+            destination=destination,
+            path=path,
+            args={"requester_user_id": requester_user_id},
+            ignore_backoff=True,
+        )
+
+    @log_function
+    def update_group_role(self, destination, group_id, requester_user_id, role_id,
+                          content):
+        """Update a role in a group
+        """
+        path = PREFIX + "/groups/%s/roles/%s" % (group_id, role_id,)
+
+        return self.client.post_json(
+            destination=destination,
+            path=path,
+            args={"requester_user_id": requester_user_id},
+            data=content,
+            ignore_backoff=True,
+        )
+
+    @log_function
+    def delete_group_role(self, destination, group_id, requester_user_id, role_id):
+        """Delete a role in a group
+        """
+        path = PREFIX + "/groups/%s/roles/%s" % (group_id, role_id,)
+
+        return self.client.delete_json(
+            destination=destination,
+            path=path,
+            args={"requester_user_id": requester_user_id},
+            ignore_backoff=True,
+        )
+
+    @log_function
+    def update_group_summary_user(self, destination, group_id, requester_user_id,
+                                  user_id, role_id, content):
+        """Update a users entry in a group
+        """
+        if role_id:
+            path = PREFIX + "/groups/%s/summary/roles/%s/users/%s" % (
+                group_id, role_id, user_id,
+            )
+        else:
+            path = PREFIX + "/groups/%s/summary/users/%s" % (group_id, user_id,)
+
+        return self.client.post_json(
+            destination=destination,
+            path=path,
+            args={"requester_user_id": requester_user_id},
+            data=content,
+            ignore_backoff=True,
+        )
+
+    @log_function
+    def delete_group_summary_user(self, destination, group_id, requester_user_id,
+                                  user_id, role_id):
+        """Delete a users entry in a group
+        """
+        if role_id:
+            path = PREFIX + "/groups/%s/summary/roles/%s/users/%s" % (
+                group_id, role_id, user_id,
+            )
+        else:
+            path = PREFIX + "/groups/%s/summary/users/%s" % (group_id, user_id,)
+
+        return self.client.delete_json(
+            destination=destination,
+            path=path,
+            args={"requester_user_id": requester_user_id},
+            ignore_backoff=True,
+        )
+
+    def bulk_get_publicised_groups(self, destination, user_ids):
+        """Get the groups a list of users are publicising
+        """
+
+        path = PREFIX + "/get_groups_publicised"
+
+        content = {"user_ids": user_ids}
+
+        return self.client.post_json(
+            destination=destination,
+            path=path,
+            data=content,
+            ignore_backoff=True,
+        )
diff --git a/synapse/federation/transport/server.py b/synapse/federation/transport/server.py
index a78f01e442..2b02b021ec 100644
--- a/synapse/federation/transport/server.py
+++ b/synapse/federation/transport/server.py
@@ -25,7 +25,7 @@ from synapse.http.servlet import (
 from synapse.util.ratelimitutils import FederationRateLimiter
 from synapse.util.versionstring import get_version_string
 from synapse.util.logcontext import preserve_fn
-from synapse.types import ThirdPartyInstanceID
+from synapse.types import ThirdPartyInstanceID, get_domain_from_id
 
 import functools
 import logging
@@ -112,7 +112,7 @@ class Authenticator(object):
                 key = strip_quotes(param_dict["key"])
                 sig = strip_quotes(param_dict["sig"])
                 return (origin, key, sig)
-            except:
+            except Exception:
                 raise AuthenticationError(
                     400, "Malformed Authorization header", Codes.UNAUTHORIZED
                 )
@@ -177,7 +177,7 @@ class BaseFederationServlet(object):
                 if self.REQUIRE_AUTH:
                     logger.exception("authenticate_request failed")
                     raise
-            except:
+            except Exception:
                 logger.exception("authenticate_request failed")
                 raise
 
@@ -270,7 +270,7 @@ class FederationSendServlet(BaseFederationServlet):
             code, response = yield self.handler.on_incoming_transaction(
                 transaction_data
             )
-        except:
+        except Exception:
             logger.exception("on_incoming_transaction failed")
             raise
 
@@ -609,6 +609,514 @@ class FederationVersionServlet(BaseFederationServlet):
         }))
 
 
+class FederationGroupsProfileServlet(BaseFederationServlet):
+    """Get/set the basic profile of a group on behalf of a user
+    """
+    PATH = "/groups/(?P<group_id>[^/]*)/profile$"
+
+    @defer.inlineCallbacks
+    def on_GET(self, origin, content, query, group_id):
+        requester_user_id = parse_string_from_args(query, "requester_user_id")
+        if get_domain_from_id(requester_user_id) != origin:
+            raise SynapseError(403, "requester_user_id doesn't match origin")
+
+        new_content = yield self.handler.get_group_profile(
+            group_id, requester_user_id
+        )
+
+        defer.returnValue((200, new_content))
+
+    @defer.inlineCallbacks
+    def on_POST(self, origin, content, query, group_id):
+        requester_user_id = parse_string_from_args(query, "requester_user_id")
+        if get_domain_from_id(requester_user_id) != origin:
+            raise SynapseError(403, "requester_user_id doesn't match origin")
+
+        new_content = yield self.handler.update_group_profile(
+            group_id, requester_user_id, content
+        )
+
+        defer.returnValue((200, new_content))
+
+
+class FederationGroupsSummaryServlet(BaseFederationServlet):
+    PATH = "/groups/(?P<group_id>[^/]*)/summary$"
+
+    @defer.inlineCallbacks
+    def on_GET(self, origin, content, query, group_id):
+        requester_user_id = parse_string_from_args(query, "requester_user_id")
+        if get_domain_from_id(requester_user_id) != origin:
+            raise SynapseError(403, "requester_user_id doesn't match origin")
+
+        new_content = yield self.handler.get_group_summary(
+            group_id, requester_user_id
+        )
+
+        defer.returnValue((200, new_content))
+
+
+class FederationGroupsRoomsServlet(BaseFederationServlet):
+    """Get the rooms in a group on behalf of a user
+    """
+    PATH = "/groups/(?P<group_id>[^/]*)/rooms$"
+
+    @defer.inlineCallbacks
+    def on_GET(self, origin, content, query, group_id):
+        requester_user_id = parse_string_from_args(query, "requester_user_id")
+        if get_domain_from_id(requester_user_id) != origin:
+            raise SynapseError(403, "requester_user_id doesn't match origin")
+
+        new_content = yield self.handler.get_rooms_in_group(
+            group_id, requester_user_id
+        )
+
+        defer.returnValue((200, new_content))
+
+
+class FederationGroupsAddRoomsServlet(BaseFederationServlet):
+    """Add/remove room from group
+    """
+    PATH = "/groups/(?P<group_id>[^/]*)/room/(?P<room_id>[^/]*)$"
+
+    @defer.inlineCallbacks
+    def on_POST(self, origin, content, query, group_id, room_id):
+        requester_user_id = parse_string_from_args(query, "requester_user_id")
+        if get_domain_from_id(requester_user_id) != origin:
+            raise SynapseError(403, "requester_user_id doesn't match origin")
+
+        new_content = yield self.handler.add_room_to_group(
+            group_id, requester_user_id, room_id, content
+        )
+
+        defer.returnValue((200, new_content))
+
+    @defer.inlineCallbacks
+    def on_DELETE(self, origin, content, query, group_id, room_id):
+        requester_user_id = parse_string_from_args(query, "requester_user_id")
+        if get_domain_from_id(requester_user_id) != origin:
+            raise SynapseError(403, "requester_user_id doesn't match origin")
+
+        new_content = yield self.handler.remove_room_from_group(
+            group_id, requester_user_id, room_id,
+        )
+
+        defer.returnValue((200, new_content))
+
+
+class FederationGroupsAddRoomsConfigServlet(BaseFederationServlet):
+    """Update room config in group
+    """
+    PATH = (
+        "/groups/(?P<group_id>[^/]*)/room/(?P<room_id>[^/]*)"
+        "/config/(?P<config_key>[^/]*)$"
+    )
+
+    @defer.inlineCallbacks
+    def on_POST(self, origin, content, query, group_id, room_id, config_key):
+        requester_user_id = parse_string_from_args(query, "requester_user_id")
+        if get_domain_from_id(requester_user_id) != origin:
+            raise SynapseError(403, "requester_user_id doesn't match origin")
+
+        result = yield self.groups_handler.update_room_in_group(
+            group_id, requester_user_id, room_id, config_key, content,
+        )
+
+        defer.returnValue((200, result))
+
+
+class FederationGroupsUsersServlet(BaseFederationServlet):
+    """Get the users in a group on behalf of a user
+    """
+    PATH = "/groups/(?P<group_id>[^/]*)/users$"
+
+    @defer.inlineCallbacks
+    def on_GET(self, origin, content, query, group_id):
+        requester_user_id = parse_string_from_args(query, "requester_user_id")
+        if get_domain_from_id(requester_user_id) != origin:
+            raise SynapseError(403, "requester_user_id doesn't match origin")
+
+        new_content = yield self.handler.get_users_in_group(
+            group_id, requester_user_id
+        )
+
+        defer.returnValue((200, new_content))
+
+
+class FederationGroupsInvitedUsersServlet(BaseFederationServlet):
+    """Get the users that have been invited to a group
+    """
+    PATH = "/groups/(?P<group_id>[^/]*)/invited_users$"
+
+    @defer.inlineCallbacks
+    def on_GET(self, origin, content, query, group_id):
+        requester_user_id = parse_string_from_args(query, "requester_user_id")
+        if get_domain_from_id(requester_user_id) != origin:
+            raise SynapseError(403, "requester_user_id doesn't match origin")
+
+        new_content = yield self.handler.get_invited_users_in_group(
+            group_id, requester_user_id
+        )
+
+        defer.returnValue((200, new_content))
+
+
+class FederationGroupsInviteServlet(BaseFederationServlet):
+    """Ask a group server to invite someone to the group
+    """
+    PATH = "/groups/(?P<group_id>[^/]*)/users/(?P<user_id>[^/]*)/invite$"
+
+    @defer.inlineCallbacks
+    def on_POST(self, origin, content, query, group_id, user_id):
+        requester_user_id = parse_string_from_args(query, "requester_user_id")
+        if get_domain_from_id(requester_user_id) != origin:
+            raise SynapseError(403, "requester_user_id doesn't match origin")
+
+        new_content = yield self.handler.invite_to_group(
+            group_id, user_id, requester_user_id, content,
+        )
+
+        defer.returnValue((200, new_content))
+
+
+class FederationGroupsAcceptInviteServlet(BaseFederationServlet):
+    """Accept an invitation from the group server
+    """
+    PATH = "/groups/(?P<group_id>[^/]*)/users/(?P<user_id>[^/]*)/accept_invite$"
+
+    @defer.inlineCallbacks
+    def on_POST(self, origin, content, query, group_id, user_id):
+        if get_domain_from_id(user_id) != origin:
+            raise SynapseError(403, "user_id doesn't match origin")
+
+        new_content = yield self.handler.accept_invite(
+            group_id, user_id, content,
+        )
+
+        defer.returnValue((200, new_content))
+
+
+class FederationGroupsRemoveUserServlet(BaseFederationServlet):
+    """Leave or kick a user from the group
+    """
+    PATH = "/groups/(?P<group_id>[^/]*)/users/(?P<user_id>[^/]*)/remove$"
+
+    @defer.inlineCallbacks
+    def on_POST(self, origin, content, query, group_id, user_id):
+        requester_user_id = parse_string_from_args(query, "requester_user_id")
+        if get_domain_from_id(requester_user_id) != origin:
+            raise SynapseError(403, "requester_user_id doesn't match origin")
+
+        new_content = yield self.handler.remove_user_from_group(
+            group_id, user_id, requester_user_id, content,
+        )
+
+        defer.returnValue((200, new_content))
+
+
+class FederationGroupsLocalInviteServlet(BaseFederationServlet):
+    """A group server has invited a local user
+    """
+    PATH = "/groups/local/(?P<group_id>[^/]*)/users/(?P<user_id>[^/]*)/invite$"
+
+    @defer.inlineCallbacks
+    def on_POST(self, origin, content, query, group_id, user_id):
+        if get_domain_from_id(group_id) != origin:
+            raise SynapseError(403, "group_id doesn't match origin")
+
+        new_content = yield self.handler.on_invite(
+            group_id, user_id, content,
+        )
+
+        defer.returnValue((200, new_content))
+
+
+class FederationGroupsRemoveLocalUserServlet(BaseFederationServlet):
+    """A group server has removed a local user
+    """
+    PATH = "/groups/local/(?P<group_id>[^/]*)/users/(?P<user_id>[^/]*)/remove$"
+
+    @defer.inlineCallbacks
+    def on_POST(self, origin, content, query, group_id, user_id):
+        if get_domain_from_id(group_id) != origin:
+            raise SynapseError(403, "user_id doesn't match origin")
+
+        new_content = yield self.handler.user_removed_from_group(
+            group_id, user_id, content,
+        )
+
+        defer.returnValue((200, new_content))
+
+
+class FederationGroupsRenewAttestaionServlet(BaseFederationServlet):
+    """A group or user's server renews their attestation
+    """
+    PATH = "/groups/(?P<group_id>[^/]*)/renew_attestation/(?P<user_id>[^/]*)$"
+
+    @defer.inlineCallbacks
+    def on_POST(self, origin, content, query, group_id, user_id):
+        # We don't need to check auth here as we check the attestation signatures
+
+        new_content = yield self.handler.on_renew_attestation(
+            group_id, user_id, content
+        )
+
+        defer.returnValue((200, new_content))
+
+
+class FederationGroupsSummaryRoomsServlet(BaseFederationServlet):
+    """Add/remove a room from the group summary, with optional category.
+
+    Matches both:
+        - /groups/:group/summary/rooms/:room_id
+        - /groups/:group/summary/categories/:category/rooms/:room_id
+    """
+    PATH = (
+        "/groups/(?P<group_id>[^/]*)/summary"
+        "(/categories/(?P<category_id>[^/]+))?"
+        "/rooms/(?P<room_id>[^/]*)$"
+    )
+
+    @defer.inlineCallbacks
+    def on_POST(self, origin, content, query, group_id, category_id, room_id):
+        requester_user_id = parse_string_from_args(query, "requester_user_id")
+        if get_domain_from_id(requester_user_id) != origin:
+            raise SynapseError(403, "requester_user_id doesn't match origin")
+
+        if category_id == "":
+            raise SynapseError(400, "category_id cannot be empty string")
+
+        resp = yield self.handler.update_group_summary_room(
+            group_id, requester_user_id,
+            room_id=room_id,
+            category_id=category_id,
+            content=content,
+        )
+
+        defer.returnValue((200, resp))
+
+    @defer.inlineCallbacks
+    def on_DELETE(self, origin, content, query, group_id, category_id, room_id):
+        requester_user_id = parse_string_from_args(query, "requester_user_id")
+        if get_domain_from_id(requester_user_id) != origin:
+            raise SynapseError(403, "requester_user_id doesn't match origin")
+
+        if category_id == "":
+            raise SynapseError(400, "category_id cannot be empty string")
+
+        resp = yield self.handler.delete_group_summary_room(
+            group_id, requester_user_id,
+            room_id=room_id,
+            category_id=category_id,
+        )
+
+        defer.returnValue((200, resp))
+
+
+class FederationGroupsCategoriesServlet(BaseFederationServlet):
+    """Get all categories for a group
+    """
+    PATH = (
+        "/groups/(?P<group_id>[^/]*)/categories/$"
+    )
+
+    @defer.inlineCallbacks
+    def on_GET(self, origin, content, query, group_id):
+        requester_user_id = parse_string_from_args(query, "requester_user_id")
+        if get_domain_from_id(requester_user_id) != origin:
+            raise SynapseError(403, "requester_user_id doesn't match origin")
+
+        resp = yield self.handler.get_group_categories(
+            group_id, requester_user_id,
+        )
+
+        defer.returnValue((200, resp))
+
+
+class FederationGroupsCategoryServlet(BaseFederationServlet):
+    """Add/remove/get a category in a group
+    """
+    PATH = (
+        "/groups/(?P<group_id>[^/]*)/categories/(?P<category_id>[^/]+)$"
+    )
+
+    @defer.inlineCallbacks
+    def on_GET(self, origin, content, query, group_id, category_id):
+        requester_user_id = parse_string_from_args(query, "requester_user_id")
+        if get_domain_from_id(requester_user_id) != origin:
+            raise SynapseError(403, "requester_user_id doesn't match origin")
+
+        resp = yield self.handler.get_group_category(
+            group_id, requester_user_id, category_id
+        )
+
+        defer.returnValue((200, resp))
+
+    @defer.inlineCallbacks
+    def on_POST(self, origin, content, query, group_id, category_id):
+        requester_user_id = parse_string_from_args(query, "requester_user_id")
+        if get_domain_from_id(requester_user_id) != origin:
+            raise SynapseError(403, "requester_user_id doesn't match origin")
+
+        if category_id == "":
+            raise SynapseError(400, "category_id cannot be empty string")
+
+        resp = yield self.handler.upsert_group_category(
+            group_id, requester_user_id, category_id, content,
+        )
+
+        defer.returnValue((200, resp))
+
+    @defer.inlineCallbacks
+    def on_DELETE(self, origin, content, query, group_id, category_id):
+        requester_user_id = parse_string_from_args(query, "requester_user_id")
+        if get_domain_from_id(requester_user_id) != origin:
+            raise SynapseError(403, "requester_user_id doesn't match origin")
+
+        if category_id == "":
+            raise SynapseError(400, "category_id cannot be empty string")
+
+        resp = yield self.handler.delete_group_category(
+            group_id, requester_user_id, category_id,
+        )
+
+        defer.returnValue((200, resp))
+
+
+class FederationGroupsRolesServlet(BaseFederationServlet):
+    """Get roles in a group
+    """
+    PATH = (
+        "/groups/(?P<group_id>[^/]*)/roles/$"
+    )
+
+    @defer.inlineCallbacks
+    def on_GET(self, origin, content, query, group_id):
+        requester_user_id = parse_string_from_args(query, "requester_user_id")
+        if get_domain_from_id(requester_user_id) != origin:
+            raise SynapseError(403, "requester_user_id doesn't match origin")
+
+        resp = yield self.handler.get_group_roles(
+            group_id, requester_user_id,
+        )
+
+        defer.returnValue((200, resp))
+
+
+class FederationGroupsRoleServlet(BaseFederationServlet):
+    """Add/remove/get a role in a group
+    """
+    PATH = (
+        "/groups/(?P<group_id>[^/]*)/roles/(?P<role_id>[^/]+)$"
+    )
+
+    @defer.inlineCallbacks
+    def on_GET(self, origin, content, query, group_id, role_id):
+        requester_user_id = parse_string_from_args(query, "requester_user_id")
+        if get_domain_from_id(requester_user_id) != origin:
+            raise SynapseError(403, "requester_user_id doesn't match origin")
+
+        resp = yield self.handler.get_group_role(
+            group_id, requester_user_id, role_id
+        )
+
+        defer.returnValue((200, resp))
+
+    @defer.inlineCallbacks
+    def on_POST(self, origin, content, query, group_id, role_id):
+        requester_user_id = parse_string_from_args(query, "requester_user_id")
+        if get_domain_from_id(requester_user_id) != origin:
+            raise SynapseError(403, "requester_user_id doesn't match origin")
+
+        if role_id == "":
+            raise SynapseError(400, "role_id cannot be empty string")
+
+        resp = yield self.handler.update_group_role(
+            group_id, requester_user_id, role_id, content,
+        )
+
+        defer.returnValue((200, resp))
+
+    @defer.inlineCallbacks
+    def on_DELETE(self, origin, content, query, group_id, role_id):
+        requester_user_id = parse_string_from_args(query, "requester_user_id")
+        if get_domain_from_id(requester_user_id) != origin:
+            raise SynapseError(403, "requester_user_id doesn't match origin")
+
+        if role_id == "":
+            raise SynapseError(400, "role_id cannot be empty string")
+
+        resp = yield self.handler.delete_group_role(
+            group_id, requester_user_id, role_id,
+        )
+
+        defer.returnValue((200, resp))
+
+
+class FederationGroupsSummaryUsersServlet(BaseFederationServlet):
+    """Add/remove a user from the group summary, with optional role.
+
+    Matches both:
+        - /groups/:group/summary/users/:user_id
+        - /groups/:group/summary/roles/:role/users/:user_id
+    """
+    PATH = (
+        "/groups/(?P<group_id>[^/]*)/summary"
+        "(/roles/(?P<role_id>[^/]+))?"
+        "/users/(?P<user_id>[^/]*)$"
+    )
+
+    @defer.inlineCallbacks
+    def on_POST(self, origin, content, query, group_id, role_id, user_id):
+        requester_user_id = parse_string_from_args(query, "requester_user_id")
+        if get_domain_from_id(requester_user_id) != origin:
+            raise SynapseError(403, "requester_user_id doesn't match origin")
+
+        if role_id == "":
+            raise SynapseError(400, "role_id cannot be empty string")
+
+        resp = yield self.handler.update_group_summary_user(
+            group_id, requester_user_id,
+            user_id=user_id,
+            role_id=role_id,
+            content=content,
+        )
+
+        defer.returnValue((200, resp))
+
+    @defer.inlineCallbacks
+    def on_DELETE(self, origin, content, query, group_id, role_id, user_id):
+        requester_user_id = parse_string_from_args(query, "requester_user_id")
+        if get_domain_from_id(requester_user_id) != origin:
+            raise SynapseError(403, "requester_user_id doesn't match origin")
+
+        if role_id == "":
+            raise SynapseError(400, "role_id cannot be empty string")
+
+        resp = yield self.handler.delete_group_summary_user(
+            group_id, requester_user_id,
+            user_id=user_id,
+            role_id=role_id,
+        )
+
+        defer.returnValue((200, resp))
+
+
+class FederationGroupsBulkPublicisedServlet(BaseFederationServlet):
+    """Get roles in a group
+    """
+    PATH = (
+        "/get_groups_publicised$"
+    )
+
+    @defer.inlineCallbacks
+    def on_POST(self, origin, content, query):
+        resp = yield self.handler.bulk_get_publicised_groups(
+            content["user_ids"], proxy=False,
+        )
+
+        defer.returnValue((200, resp))
+
+
 FEDERATION_SERVLET_CLASSES = (
     FederationSendServlet,
     FederationPullServlet,
@@ -635,10 +1143,42 @@ FEDERATION_SERVLET_CLASSES = (
     FederationVersionServlet,
 )
 
+
 ROOM_LIST_CLASSES = (
     PublicRoomList,
 )
 
+GROUP_SERVER_SERVLET_CLASSES = (
+    FederationGroupsProfileServlet,
+    FederationGroupsSummaryServlet,
+    FederationGroupsRoomsServlet,
+    FederationGroupsUsersServlet,
+    FederationGroupsInvitedUsersServlet,
+    FederationGroupsInviteServlet,
+    FederationGroupsAcceptInviteServlet,
+    FederationGroupsRemoveUserServlet,
+    FederationGroupsSummaryRoomsServlet,
+    FederationGroupsCategoriesServlet,
+    FederationGroupsCategoryServlet,
+    FederationGroupsRolesServlet,
+    FederationGroupsRoleServlet,
+    FederationGroupsSummaryUsersServlet,
+    FederationGroupsAddRoomsServlet,
+    FederationGroupsAddRoomsConfigServlet,
+)
+
+
+GROUP_LOCAL_SERVLET_CLASSES = (
+    FederationGroupsLocalInviteServlet,
+    FederationGroupsRemoveLocalUserServlet,
+    FederationGroupsBulkPublicisedServlet,
+)
+
+
+GROUP_ATTESTATION_SERVLET_CLASSES = (
+    FederationGroupsRenewAttestaionServlet,
+)
+
 
 def register_servlets(hs, resource, authenticator, ratelimiter):
     for servletclass in FEDERATION_SERVLET_CLASSES:
@@ -656,3 +1196,27 @@ def register_servlets(hs, resource, authenticator, ratelimiter):
             ratelimiter=ratelimiter,
             server_name=hs.hostname,
         ).register(resource)
+
+    for servletclass in GROUP_SERVER_SERVLET_CLASSES:
+        servletclass(
+            handler=hs.get_groups_server_handler(),
+            authenticator=authenticator,
+            ratelimiter=ratelimiter,
+            server_name=hs.hostname,
+        ).register(resource)
+
+    for servletclass in GROUP_LOCAL_SERVLET_CLASSES:
+        servletclass(
+            handler=hs.get_groups_local_handler(),
+            authenticator=authenticator,
+            ratelimiter=ratelimiter,
+            server_name=hs.hostname,
+        ).register(resource)
+
+    for servletclass in GROUP_ATTESTATION_SERVLET_CLASSES:
+        servletclass(
+            handler=hs.get_groups_attestation_renewer(),
+            authenticator=authenticator,
+            ratelimiter=ratelimiter,
+            server_name=hs.hostname,
+        ).register(resource)
diff --git a/synapse/groups/__init__.py b/synapse/groups/__init__.py
new file mode 100644
index 0000000000..e69de29bb2
--- /dev/null
+++ b/synapse/groups/__init__.py
diff --git a/synapse/groups/attestations.py b/synapse/groups/attestations.py
new file mode 100644
index 0000000000..1fb709e6c3
--- /dev/null
+++ b/synapse/groups/attestations.py
@@ -0,0 +1,195 @@
+# -*- coding: utf-8 -*-
+# Copyright 2017 Vector Creations Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""Attestations ensure that users and groups can't lie about their memberships.
+
+When a user joins a group the HS and GS swap attestations, which allow them
+both to independently prove to third parties their membership.These
+attestations have a validity period so need to be periodically renewed.
+
+If a user leaves (or gets kicked out of) a group, either side can still use
+their attestation to "prove" their membership, until the attestation expires.
+Therefore attestations shouldn't be relied on to prove membership in important
+cases, but can for less important situtations, e.g. showing a users membership
+of groups on their profile, showing flairs, etc.abs
+
+An attestsation is a signed blob of json that looks like:
+
+    {
+        "user_id": "@foo:a.example.com",
+        "group_id": "+bar:b.example.com",
+        "valid_until_ms": 1507994728530,
+        "signatures":{"matrix.org":{"ed25519:auto":"..."}}
+    }
+"""
+
+import logging
+import random
+
+from twisted.internet import defer
+
+from synapse.api.errors import SynapseError
+from synapse.types import get_domain_from_id
+from synapse.util.logcontext import preserve_fn
+
+from signedjson.sign import sign_json
+
+
+logger = logging.getLogger(__name__)
+
+
+# Default validity duration for new attestations we create
+DEFAULT_ATTESTATION_LENGTH_MS = 3 * 24 * 60 * 60 * 1000
+
+# We add some jitter to the validity duration of attestations so that if we
+# add lots of users at once we don't need to renew them all at once.
+# The jitter is a multiplier picked randomly between the first and second number
+DEFAULT_ATTESTATION_JITTER = (0.9, 1.3)
+
+# Start trying to update our attestations when they come this close to expiring
+UPDATE_ATTESTATION_TIME_MS = 1 * 24 * 60 * 60 * 1000
+
+
+class GroupAttestationSigning(object):
+    """Creates and verifies group attestations.
+    """
+    def __init__(self, hs):
+        self.keyring = hs.get_keyring()
+        self.clock = hs.get_clock()
+        self.server_name = hs.hostname
+        self.signing_key = hs.config.signing_key[0]
+
+    @defer.inlineCallbacks
+    def verify_attestation(self, attestation, group_id, user_id, server_name=None):
+        """Verifies that the given attestation matches the given parameters.
+
+        An optional server_name can be supplied to explicitly set which server's
+        signature is expected. Otherwise assumes that either the group_id or user_id
+        is local and uses the other's server as the one to check.
+        """
+
+        if not server_name:
+            if get_domain_from_id(group_id) == self.server_name:
+                server_name = get_domain_from_id(user_id)
+            elif get_domain_from_id(user_id) == self.server_name:
+                server_name = get_domain_from_id(group_id)
+            else:
+                raise Exception("Expected either group_id or user_id to be local")
+
+        if user_id != attestation["user_id"]:
+            raise SynapseError(400, "Attestation has incorrect user_id")
+
+        if group_id != attestation["group_id"]:
+            raise SynapseError(400, "Attestation has incorrect group_id")
+        valid_until_ms = attestation["valid_until_ms"]
+
+        # TODO: We also want to check that *new* attestations that people give
+        # us to store are valid for at least a little while.
+        if valid_until_ms < self.clock.time_msec():
+            raise SynapseError(400, "Attestation expired")
+
+        yield self.keyring.verify_json_for_server(server_name, attestation)
+
+    def create_attestation(self, group_id, user_id):
+        """Create an attestation for the group_id and user_id with default
+        validity length.
+        """
+        validity_period = DEFAULT_ATTESTATION_LENGTH_MS
+        validity_period *= random.uniform(*DEFAULT_ATTESTATION_JITTER)
+        valid_until_ms = int(self.clock.time_msec() + validity_period)
+
+        return sign_json({
+            "group_id": group_id,
+            "user_id": user_id,
+            "valid_until_ms": valid_until_ms,
+        }, self.server_name, self.signing_key)
+
+
+class GroupAttestionRenewer(object):
+    """Responsible for sending and receiving attestation updates.
+    """
+
+    def __init__(self, hs):
+        self.clock = hs.get_clock()
+        self.store = hs.get_datastore()
+        self.assestations = hs.get_groups_attestation_signing()
+        self.transport_client = hs.get_federation_transport_client()
+        self.is_mine_id = hs.is_mine_id
+        self.attestations = hs.get_groups_attestation_signing()
+
+        self._renew_attestations_loop = self.clock.looping_call(
+            self._renew_attestations, 30 * 60 * 1000,
+        )
+
+    @defer.inlineCallbacks
+    def on_renew_attestation(self, group_id, user_id, content):
+        """When a remote updates an attestation
+        """
+        attestation = content["attestation"]
+
+        if not self.is_mine_id(group_id) and not self.is_mine_id(user_id):
+            raise SynapseError(400, "Neither user not group are on this server")
+
+        yield self.attestations.verify_attestation(
+            attestation,
+            user_id=user_id,
+            group_id=group_id,
+        )
+
+        yield self.store.update_remote_attestion(group_id, user_id, attestation)
+
+        defer.returnValue({})
+
+    @defer.inlineCallbacks
+    def _renew_attestations(self):
+        """Called periodically to check if we need to update any of our attestations
+        """
+
+        now = self.clock.time_msec()
+
+        rows = yield self.store.get_attestations_need_renewals(
+            now + UPDATE_ATTESTATION_TIME_MS
+        )
+
+        @defer.inlineCallbacks
+        def _renew_attestation(group_id, user_id):
+            if not self.is_mine_id(group_id):
+                destination = get_domain_from_id(group_id)
+            elif not self.is_mine_id(user_id):
+                destination = get_domain_from_id(user_id)
+            else:
+                logger.warn(
+                    "Incorrectly trying to do attestations for user: %r in %r",
+                    user_id, group_id,
+                )
+                yield self.store.remove_attestation_renewal(group_id, user_id)
+                return
+
+            attestation = self.attestations.create_attestation(group_id, user_id)
+
+            yield self.transport_client.renew_group_attestation(
+                destination, group_id, user_id,
+                content={"attestation": attestation},
+            )
+
+            yield self.store.update_attestation_renewal(
+                group_id, user_id, attestation
+            )
+
+        for row in rows:
+            group_id = row["group_id"]
+            user_id = row["user_id"]
+
+            preserve_fn(_renew_attestation)(group_id, user_id)
diff --git a/synapse/groups/groups_server.py b/synapse/groups/groups_server.py
new file mode 100644
index 0000000000..0b995aed70
--- /dev/null
+++ b/synapse/groups/groups_server.py
@@ -0,0 +1,864 @@
+# -*- coding: utf-8 -*-
+# Copyright 2017 Vector Creations Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import logging
+
+from synapse.api.errors import SynapseError
+from synapse.types import GroupID, RoomID, UserID, get_domain_from_id
+from twisted.internet import defer
+
+logger = logging.getLogger(__name__)
+
+
+# TODO: Allow users to "knock" or simpkly join depending on rules
+# TODO: Federation admin APIs
+# TODO: is_priveged flag to users and is_public to users and rooms
+# TODO: Audit log for admins (profile updates, membership changes, users who tried
+#       to join but were rejected, etc)
+# TODO: Flairs
+
+
+class GroupsServerHandler(object):
+    def __init__(self, hs):
+        self.hs = hs
+        self.store = hs.get_datastore()
+        self.room_list_handler = hs.get_room_list_handler()
+        self.auth = hs.get_auth()
+        self.clock = hs.get_clock()
+        self.keyring = hs.get_keyring()
+        self.is_mine_id = hs.is_mine_id
+        self.signing_key = hs.config.signing_key[0]
+        self.server_name = hs.hostname
+        self.attestations = hs.get_groups_attestation_signing()
+        self.transport_client = hs.get_federation_transport_client()
+        self.profile_handler = hs.get_profile_handler()
+
+        # Ensure attestations get renewed
+        hs.get_groups_attestation_renewer()
+
+    @defer.inlineCallbacks
+    def check_group_is_ours(self, group_id, requester_user_id,
+                            and_exists=False, and_is_admin=None):
+        """Check that the group is ours, and optionally if it exists.
+
+        If group does exist then return group.
+
+        Args:
+            group_id (str)
+            and_exists (bool): whether to also check if group exists
+            and_is_admin (str): whether to also check if given str is a user_id
+                that is an admin
+        """
+        if not self.is_mine_id(group_id):
+            raise SynapseError(400, "Group not on this server")
+
+        group = yield self.store.get_group(group_id)
+        if and_exists and not group:
+            raise SynapseError(404, "Unknown group")
+
+        is_user_in_group = yield self.store.is_user_in_group(requester_user_id, group_id)
+        if group and not is_user_in_group and not group["is_public"]:
+            raise SynapseError(404, "Unknown group")
+
+        if and_is_admin:
+            is_admin = yield self.store.is_user_admin_in_group(group_id, and_is_admin)
+            if not is_admin:
+                raise SynapseError(403, "User is not admin in group")
+
+        defer.returnValue(group)
+
+    @defer.inlineCallbacks
+    def get_group_summary(self, group_id, requester_user_id):
+        """Get the summary for a group as seen by requester_user_id.
+
+        The group summary consists of the profile of the room, and a curated
+        list of users and rooms. These list *may* be organised by role/category.
+        The roles/categories are ordered, and so are the users/rooms within them.
+
+        A user/room may appear in multiple roles/categories.
+        """
+        yield self.check_group_is_ours(group_id, requester_user_id, and_exists=True)
+
+        is_user_in_group = yield self.store.is_user_in_group(requester_user_id, group_id)
+
+        profile = yield self.get_group_profile(group_id, requester_user_id)
+
+        users, roles = yield self.store.get_users_for_summary_by_role(
+            group_id, include_private=is_user_in_group,
+        )
+
+        # TODO: Add profiles to users
+
+        rooms, categories = yield self.store.get_rooms_for_summary_by_category(
+            group_id, include_private=is_user_in_group,
+        )
+
+        for room_entry in rooms:
+            room_id = room_entry["room_id"]
+            joined_users = yield self.store.get_users_in_room(room_id)
+            entry = yield self.room_list_handler.generate_room_entry(
+                room_id, len(joined_users),
+                with_alias=False, allow_private=True,
+            )
+            entry = dict(entry)  # so we don't change whats cached
+            entry.pop("room_id", None)
+
+            room_entry["profile"] = entry
+
+        rooms.sort(key=lambda e: e.get("order", 0))
+
+        for entry in users:
+            user_id = entry["user_id"]
+
+            if not self.is_mine_id(requester_user_id):
+                attestation = yield self.store.get_remote_attestation(group_id, user_id)
+                if not attestation:
+                    continue
+
+                entry["attestation"] = attestation
+            else:
+                entry["attestation"] = self.attestations.create_attestation(
+                    group_id, user_id,
+                )
+
+            user_profile = yield self.profile_handler.get_profile_from_cache(user_id)
+            entry.update(user_profile)
+
+        users.sort(key=lambda e: e.get("order", 0))
+
+        membership_info = yield self.store.get_users_membership_info_in_group(
+            group_id, requester_user_id,
+        )
+
+        defer.returnValue({
+            "profile": profile,
+            "users_section": {
+                "users": users,
+                "roles": roles,
+                "total_user_count_estimate": 0,  # TODO
+            },
+            "rooms_section": {
+                "rooms": rooms,
+                "categories": categories,
+                "total_room_count_estimate": 0,  # TODO
+            },
+            "user": membership_info,
+        })
+
+    @defer.inlineCallbacks
+    def update_group_summary_room(self, group_id, requester_user_id,
+                                  room_id, category_id, content):
+        """Add/update a room to the group summary
+        """
+        yield self.check_group_is_ours(
+            group_id,
+            requester_user_id,
+            and_exists=True,
+            and_is_admin=requester_user_id,
+        )
+
+        RoomID.from_string(room_id)  # Ensure valid room id
+
+        order = content.get("order", None)
+
+        is_public = _parse_visibility_from_contents(content)
+
+        yield self.store.add_room_to_summary(
+            group_id=group_id,
+            room_id=room_id,
+            category_id=category_id,
+            order=order,
+            is_public=is_public,
+        )
+
+        defer.returnValue({})
+
+    @defer.inlineCallbacks
+    def delete_group_summary_room(self, group_id, requester_user_id,
+                                  room_id, category_id):
+        """Remove a room from the summary
+        """
+        yield self.check_group_is_ours(
+            group_id,
+            requester_user_id,
+            and_exists=True,
+            and_is_admin=requester_user_id,
+        )
+
+        yield self.store.remove_room_from_summary(
+            group_id=group_id,
+            room_id=room_id,
+            category_id=category_id,
+        )
+
+        defer.returnValue({})
+
+    @defer.inlineCallbacks
+    def get_group_categories(self, group_id, requester_user_id):
+        """Get all categories in a group (as seen by user)
+        """
+        yield self.check_group_is_ours(group_id, requester_user_id, and_exists=True)
+
+        categories = yield self.store.get_group_categories(
+            group_id=group_id,
+        )
+        defer.returnValue({"categories": categories})
+
+    @defer.inlineCallbacks
+    def get_group_category(self, group_id, requester_user_id, category_id):
+        """Get a specific category in a group (as seen by user)
+        """
+        yield self.check_group_is_ours(group_id, requester_user_id, and_exists=True)
+
+        res = yield self.store.get_group_category(
+            group_id=group_id,
+            category_id=category_id,
+        )
+
+        defer.returnValue(res)
+
+    @defer.inlineCallbacks
+    def update_group_category(self, group_id, requester_user_id, category_id, content):
+        """Add/Update a group category
+        """
+        yield self.check_group_is_ours(
+            group_id,
+            requester_user_id,
+            and_exists=True,
+            and_is_admin=requester_user_id,
+        )
+
+        is_public = _parse_visibility_from_contents(content)
+        profile = content.get("profile")
+
+        yield self.store.upsert_group_category(
+            group_id=group_id,
+            category_id=category_id,
+            is_public=is_public,
+            profile=profile,
+        )
+
+        defer.returnValue({})
+
+    @defer.inlineCallbacks
+    def delete_group_category(self, group_id, requester_user_id, category_id):
+        """Delete a group category
+        """
+        yield self.check_group_is_ours(
+            group_id,
+            requester_user_id,
+            and_exists=True,
+            and_is_admin=requester_user_id
+        )
+
+        yield self.store.remove_group_category(
+            group_id=group_id,
+            category_id=category_id,
+        )
+
+        defer.returnValue({})
+
+    @defer.inlineCallbacks
+    def get_group_roles(self, group_id, requester_user_id):
+        """Get all roles in a group (as seen by user)
+        """
+        yield self.check_group_is_ours(group_id, requester_user_id, and_exists=True)
+
+        roles = yield self.store.get_group_roles(
+            group_id=group_id,
+        )
+        defer.returnValue({"roles": roles})
+
+    @defer.inlineCallbacks
+    def get_group_role(self, group_id, requester_user_id, role_id):
+        """Get a specific role in a group (as seen by user)
+        """
+        yield self.check_group_is_ours(group_id, requester_user_id, and_exists=True)
+
+        res = yield self.store.get_group_role(
+            group_id=group_id,
+            role_id=role_id,
+        )
+        defer.returnValue(res)
+
+    @defer.inlineCallbacks
+    def update_group_role(self, group_id, requester_user_id, role_id, content):
+        """Add/update a role in a group
+        """
+        yield self.check_group_is_ours(
+            group_id,
+            requester_user_id,
+            and_exists=True,
+            and_is_admin=requester_user_id,
+        )
+
+        is_public = _parse_visibility_from_contents(content)
+
+        profile = content.get("profile")
+
+        yield self.store.upsert_group_role(
+            group_id=group_id,
+            role_id=role_id,
+            is_public=is_public,
+            profile=profile,
+        )
+
+        defer.returnValue({})
+
+    @defer.inlineCallbacks
+    def delete_group_role(self, group_id, requester_user_id, role_id):
+        """Remove role from group
+        """
+        yield self.check_group_is_ours(
+            group_id,
+            requester_user_id,
+            and_exists=True,
+            and_is_admin=requester_user_id,
+        )
+
+        yield self.store.remove_group_role(
+            group_id=group_id,
+            role_id=role_id,
+        )
+
+        defer.returnValue({})
+
+    @defer.inlineCallbacks
+    def update_group_summary_user(self, group_id, requester_user_id, user_id, role_id,
+                                  content):
+        """Add/update a users entry in the group summary
+        """
+        yield self.check_group_is_ours(
+            group_id, requester_user_id, and_exists=True, and_is_admin=requester_user_id,
+        )
+
+        order = content.get("order", None)
+
+        is_public = _parse_visibility_from_contents(content)
+
+        yield self.store.add_user_to_summary(
+            group_id=group_id,
+            user_id=user_id,
+            role_id=role_id,
+            order=order,
+            is_public=is_public,
+        )
+
+        defer.returnValue({})
+
+    @defer.inlineCallbacks
+    def delete_group_summary_user(self, group_id, requester_user_id, user_id, role_id):
+        """Remove a user from the group summary
+        """
+        yield self.check_group_is_ours(
+            group_id, requester_user_id, and_exists=True, and_is_admin=requester_user_id,
+        )
+
+        yield self.store.remove_user_from_summary(
+            group_id=group_id,
+            user_id=user_id,
+            role_id=role_id,
+        )
+
+        defer.returnValue({})
+
+    @defer.inlineCallbacks
+    def get_group_profile(self, group_id, requester_user_id):
+        """Get the group profile as seen by requester_user_id
+        """
+
+        yield self.check_group_is_ours(group_id, requester_user_id)
+
+        group_description = yield self.store.get_group(group_id)
+
+        if group_description:
+            defer.returnValue(group_description)
+        else:
+            raise SynapseError(404, "Unknown group")
+
+    @defer.inlineCallbacks
+    def update_group_profile(self, group_id, requester_user_id, content):
+        """Update the group profile
+        """
+        yield self.check_group_is_ours(
+            group_id, requester_user_id, and_exists=True, and_is_admin=requester_user_id,
+        )
+
+        profile = {}
+        for keyname in ("name", "avatar_url", "short_description",
+                        "long_description"):
+            if keyname in content:
+                value = content[keyname]
+                if not isinstance(value, basestring):
+                    raise SynapseError(400, "%r value is not a string" % (keyname,))
+                profile[keyname] = value
+
+        yield self.store.update_group_profile(group_id, profile)
+
+    @defer.inlineCallbacks
+    def get_users_in_group(self, group_id, requester_user_id):
+        """Get the users in group as seen by requester_user_id.
+
+        The ordering is arbitrary at the moment
+        """
+
+        yield self.check_group_is_ours(group_id, requester_user_id, and_exists=True)
+
+        is_user_in_group = yield self.store.is_user_in_group(requester_user_id, group_id)
+
+        user_results = yield self.store.get_users_in_group(
+            group_id, include_private=is_user_in_group,
+        )
+
+        chunk = []
+        for user_result in user_results:
+            g_user_id = user_result["user_id"]
+            is_public = user_result["is_public"]
+            is_privileged = user_result["is_admin"]
+
+            entry = {"user_id": g_user_id}
+
+            profile = yield self.profile_handler.get_profile_from_cache(g_user_id)
+            entry.update(profile)
+
+            entry["is_public"] = bool(is_public)
+            entry["is_privileged"] = bool(is_privileged)
+
+            if not self.is_mine_id(g_user_id):
+                attestation = yield self.store.get_remote_attestation(group_id, g_user_id)
+                if not attestation:
+                    continue
+
+                entry["attestation"] = attestation
+            else:
+                entry["attestation"] = self.attestations.create_attestation(
+                    group_id, g_user_id,
+                )
+
+            chunk.append(entry)
+
+        # TODO: If admin add lists of users whose attestations have timed out
+
+        defer.returnValue({
+            "chunk": chunk,
+            "total_user_count_estimate": len(user_results),
+        })
+
+    @defer.inlineCallbacks
+    def get_invited_users_in_group(self, group_id, requester_user_id):
+        """Get the users that have been invited to a group as seen by requester_user_id.
+
+        The ordering is arbitrary at the moment
+        """
+
+        yield self.check_group_is_ours(group_id, requester_user_id, and_exists=True)
+
+        is_user_in_group = yield self.store.is_user_in_group(requester_user_id, group_id)
+
+        if not is_user_in_group:
+            raise SynapseError(403, "User not in group")
+
+        invited_users = yield self.store.get_invited_users_in_group(group_id)
+
+        user_profiles = []
+
+        for user_id in invited_users:
+            user_profile = {
+                "user_id": user_id
+            }
+            try:
+                profile = yield self.profile_handler.get_profile_from_cache(user_id)
+                user_profile.update(profile)
+            except Exception as e:
+                logger.warn("Error getting profile for %s: %s", user_id, e)
+            user_profiles.append(user_profile)
+
+        defer.returnValue({
+            "chunk": user_profiles,
+            "total_user_count_estimate": len(invited_users),
+        })
+
+    @defer.inlineCallbacks
+    def get_rooms_in_group(self, group_id, requester_user_id):
+        """Get the rooms in group as seen by requester_user_id
+
+        This returns rooms in order of decreasing number of joined users
+        """
+
+        yield self.check_group_is_ours(group_id, requester_user_id, and_exists=True)
+
+        is_user_in_group = yield self.store.is_user_in_group(requester_user_id, group_id)
+
+        room_results = yield self.store.get_rooms_in_group(
+            group_id, include_private=is_user_in_group,
+        )
+
+        chunk = []
+        for room_result in room_results:
+            room_id = room_result["room_id"]
+
+            joined_users = yield self.store.get_users_in_room(room_id)
+            entry = yield self.room_list_handler.generate_room_entry(
+                room_id, len(joined_users),
+                with_alias=False, allow_private=True,
+            )
+
+            if not entry:
+                continue
+
+            entry["is_public"] = bool(room_result["is_public"])
+
+            chunk.append(entry)
+
+        chunk.sort(key=lambda e: -e["num_joined_members"])
+
+        defer.returnValue({
+            "chunk": chunk,
+            "total_room_count_estimate": len(room_results),
+        })
+
+    @defer.inlineCallbacks
+    def add_room_to_group(self, group_id, requester_user_id, room_id, content):
+        """Add room to group
+        """
+        RoomID.from_string(room_id)  # Ensure valid room id
+
+        yield self.check_group_is_ours(
+            group_id, requester_user_id, and_exists=True, and_is_admin=requester_user_id
+        )
+
+        is_public = _parse_visibility_from_contents(content)
+
+        yield self.store.add_room_to_group(group_id, room_id, is_public=is_public)
+
+        defer.returnValue({})
+
+    @defer.inlineCallbacks
+    def update_room_in_group(self, group_id, requester_user_id, room_id, config_key,
+                             content):
+        """Update room in group
+        """
+        RoomID.from_string(room_id)  # Ensure valid room id
+
+        yield self.check_group_is_ours(
+            group_id, requester_user_id, and_exists=True, and_is_admin=requester_user_id
+        )
+
+        if config_key == "m.visibility":
+            is_public = _parse_visibility_dict(content)
+
+            yield self.store.update_room_in_group_visibility(
+                group_id, room_id,
+                is_public=is_public,
+            )
+        else:
+            raise SynapseError(400, "Uknown config option")
+
+        defer.returnValue({})
+
+    @defer.inlineCallbacks
+    def remove_room_from_group(self, group_id, requester_user_id, room_id):
+        """Remove room from group
+        """
+        yield self.check_group_is_ours(
+            group_id, requester_user_id, and_exists=True, and_is_admin=requester_user_id
+        )
+
+        yield self.store.remove_room_from_group(group_id, room_id)
+
+        defer.returnValue({})
+
+    @defer.inlineCallbacks
+    def invite_to_group(self, group_id, user_id, requester_user_id, content):
+        """Invite user to group
+        """
+
+        group = yield self.check_group_is_ours(
+            group_id, requester_user_id, and_exists=True, and_is_admin=requester_user_id
+        )
+
+        # TODO: Check if user knocked
+        # TODO: Check if user is already invited
+
+        content = {
+            "profile": {
+                "name": group["name"],
+                "avatar_url": group["avatar_url"],
+            },
+            "inviter": requester_user_id,
+        }
+
+        if self.hs.is_mine_id(user_id):
+            groups_local = self.hs.get_groups_local_handler()
+            res = yield groups_local.on_invite(group_id, user_id, content)
+            local_attestation = None
+        else:
+            local_attestation = self.attestations.create_attestation(group_id, user_id)
+            content.update({
+                "attestation": local_attestation,
+            })
+
+            res = yield self.transport_client.invite_to_group_notification(
+                get_domain_from_id(user_id), group_id, user_id, content
+            )
+
+            user_profile = res.get("user_profile", {})
+            yield self.store.add_remote_profile_cache(
+                user_id,
+                displayname=user_profile.get("displayname"),
+                avatar_url=user_profile.get("avatar_url"),
+            )
+
+        if res["state"] == "join":
+            if not self.hs.is_mine_id(user_id):
+                remote_attestation = res["attestation"]
+
+                yield self.attestations.verify_attestation(
+                    remote_attestation,
+                    user_id=user_id,
+                    group_id=group_id,
+                )
+            else:
+                remote_attestation = None
+
+            yield self.store.add_user_to_group(
+                group_id, user_id,
+                is_admin=False,
+                is_public=False,  # TODO
+                local_attestation=local_attestation,
+                remote_attestation=remote_attestation,
+            )
+        elif res["state"] == "invite":
+            yield self.store.add_group_invite(
+                group_id, user_id,
+            )
+            defer.returnValue({
+                "state": "invite"
+            })
+        elif res["state"] == "reject":
+            defer.returnValue({
+                "state": "reject"
+            })
+        else:
+            raise SynapseError(502, "Unknown state returned by HS")
+
+    @defer.inlineCallbacks
+    def accept_invite(self, group_id, requester_user_id, content):
+        """User tries to accept an invite to the group.
+
+        This is different from them asking to join, and so should error if no
+        invite exists (and they're not a member of the group)
+        """
+
+        yield self.check_group_is_ours(group_id, requester_user_id, and_exists=True)
+
+        is_invited = yield self.store.is_user_invited_to_local_group(
+            group_id, requester_user_id,
+        )
+        if not is_invited:
+            raise SynapseError(403, "User not invited to group")
+
+        if not self.hs.is_mine_id(requester_user_id):
+            local_attestation = self.attestations.create_attestation(
+                group_id, requester_user_id,
+            )
+            remote_attestation = content["attestation"]
+
+            yield self.attestations.verify_attestation(
+                remote_attestation,
+                user_id=requester_user_id,
+                group_id=group_id,
+            )
+        else:
+            local_attestation = None
+            remote_attestation = None
+
+        is_public = _parse_visibility_from_contents(content)
+
+        yield self.store.add_user_to_group(
+            group_id, requester_user_id,
+            is_admin=False,
+            is_public=is_public,
+            local_attestation=local_attestation,
+            remote_attestation=remote_attestation,
+        )
+
+        defer.returnValue({
+            "state": "join",
+            "attestation": local_attestation,
+        })
+
+    @defer.inlineCallbacks
+    def knock(self, group_id, requester_user_id, content):
+        """A user requests becoming a member of the group
+        """
+        yield self.check_group_is_ours(group_id, requester_user_id, and_exists=True)
+
+        raise NotImplementedError()
+
+    @defer.inlineCallbacks
+    def accept_knock(self, group_id, requester_user_id, content):
+        """Accept a users knock to the room.
+
+        Errors if the user hasn't knocked, rather than inviting them.
+        """
+
+        yield self.check_group_is_ours(group_id, requester_user_id, and_exists=True)
+
+        raise NotImplementedError()
+
+    @defer.inlineCallbacks
+    def remove_user_from_group(self, group_id, user_id, requester_user_id, content):
+        """Remove a user from the group; either a user is leaving or an admin
+        kicked them.
+        """
+
+        yield self.check_group_is_ours(group_id, requester_user_id, and_exists=True)
+
+        is_kick = False
+        if requester_user_id != user_id:
+            is_admin = yield self.store.is_user_admin_in_group(
+                group_id, requester_user_id
+            )
+            if not is_admin:
+                raise SynapseError(403, "User is not admin in group")
+
+            is_kick = True
+
+        yield self.store.remove_user_from_group(
+            group_id, user_id,
+        )
+
+        if is_kick:
+            if self.hs.is_mine_id(user_id):
+                groups_local = self.hs.get_groups_local_handler()
+                yield groups_local.user_removed_from_group(group_id, user_id, {})
+            else:
+                yield self.transport_client.remove_user_from_group_notification(
+                    get_domain_from_id(user_id), group_id, user_id, {}
+                )
+
+        if not self.hs.is_mine_id(user_id):
+            yield self.store.maybe_delete_remote_profile_cache(user_id)
+
+        defer.returnValue({})
+
+    @defer.inlineCallbacks
+    def create_group(self, group_id, requester_user_id, content):
+        group = yield self.check_group_is_ours(group_id, requester_user_id)
+
+        logger.info("Attempting to create group with ID: %r", group_id)
+
+        # parsing the id into a GroupID validates it.
+        group_id_obj = GroupID.from_string(group_id)
+
+        if group:
+            raise SynapseError(400, "Group already exists")
+
+        is_admin = yield self.auth.is_server_admin(UserID.from_string(requester_user_id))
+        if not is_admin:
+            if not self.hs.config.enable_group_creation:
+                raise SynapseError(
+                    403, "Only a server admin can create groups on this server",
+                )
+            localpart = group_id_obj.localpart
+            if not localpart.startswith(self.hs.config.group_creation_prefix):
+                raise SynapseError(
+                    400,
+                    "Can only create groups with prefix %r on this server" % (
+                        self.hs.config.group_creation_prefix,
+                    ),
+                )
+
+        profile = content.get("profile", {})
+        name = profile.get("name")
+        avatar_url = profile.get("avatar_url")
+        short_description = profile.get("short_description")
+        long_description = profile.get("long_description")
+        user_profile = content.get("user_profile", {})
+
+        yield self.store.create_group(
+            group_id,
+            requester_user_id,
+            name=name,
+            avatar_url=avatar_url,
+            short_description=short_description,
+            long_description=long_description,
+        )
+
+        if not self.hs.is_mine_id(requester_user_id):
+            remote_attestation = content["attestation"]
+
+            yield self.attestations.verify_attestation(
+                remote_attestation,
+                user_id=requester_user_id,
+                group_id=group_id,
+            )
+
+            local_attestation = self.attestations.create_attestation(
+                group_id,
+                requester_user_id,
+            )
+        else:
+            local_attestation = None
+            remote_attestation = None
+
+        yield self.store.add_user_to_group(
+            group_id, requester_user_id,
+            is_admin=True,
+            is_public=True,  # TODO
+            local_attestation=local_attestation,
+            remote_attestation=remote_attestation,
+        )
+
+        if not self.hs.is_mine_id(requester_user_id):
+            yield self.store.add_remote_profile_cache(
+                requester_user_id,
+                displayname=user_profile.get("displayname"),
+                avatar_url=user_profile.get("avatar_url"),
+            )
+
+        defer.returnValue({
+            "group_id": group_id,
+        })
+
+
+def _parse_visibility_from_contents(content):
+    """Given a content for a request parse out whether the entity should be
+    public or not
+    """
+
+    visibility = content.get("m.visibility")
+    if visibility:
+        return _parse_visibility_dict(visibility)
+    else:
+        is_public = True
+
+    return is_public
+
+
+def _parse_visibility_dict(visibility):
+    """Given a dict for the "m.visibility" config return if the entity should
+    be public or not
+    """
+    vis_type = visibility.get("type")
+    if not vis_type:
+        return True
+
+    if vis_type not in ("public", "private"):
+        raise SynapseError(
+            400, "Synapse only supports 'public'/'private' visibility"
+        )
+    return vis_type == "public"
diff --git a/synapse/handlers/__init__.py b/synapse/handlers/__init__.py
index 5ad408f549..53213cdccf 100644
--- a/synapse/handlers/__init__.py
+++ b/synapse/handlers/__init__.py
@@ -20,7 +20,6 @@ from .room import (
 from .room_member import RoomMemberHandler
 from .message import MessageHandler
 from .federation import FederationHandler
-from .profile import ProfileHandler
 from .directory import DirectoryHandler
 from .admin import AdminHandler
 from .identity import IdentityHandler
@@ -52,7 +51,6 @@ class Handlers(object):
         self.room_creation_handler = RoomCreationHandler(hs)
         self.room_member_handler = RoomMemberHandler(hs)
         self.federation_handler = FederationHandler(hs)
-        self.profile_handler = ProfileHandler(hs)
         self.directory_handler = DirectoryHandler(hs)
         self.admin_handler = AdminHandler(hs)
         self.identity_handler = IdentityHandler(hs)
diff --git a/synapse/handlers/appservice.py b/synapse/handlers/appservice.py
index 05af54d31b..feca3e4c10 100644
--- a/synapse/handlers/appservice.py
+++ b/synapse/handlers/appservice.py
@@ -17,7 +17,7 @@ from twisted.internet import defer
 
 from synapse.api.constants import EventTypes
 from synapse.util.metrics import Measure
-from synapse.util.logcontext import preserve_fn, preserve_context_over_deferred
+from synapse.util.logcontext import make_deferred_yieldable, preserve_fn
 
 import logging
 
@@ -70,11 +70,10 @@ class ApplicationServicesHandler(object):
         with Measure(self.clock, "notify_interested_services"):
             self.is_processing = True
             try:
-                upper_bound = self.current_max
                 limit = 100
                 while True:
                     upper_bound, events = yield self.store.get_new_events_for_appservice(
-                        upper_bound, limit
+                        self.current_max, limit
                     )
 
                     if not events:
@@ -105,9 +104,6 @@ class ApplicationServicesHandler(object):
                             )
 
                     yield self.store.set_appservice_last_pos(upper_bound)
-
-                    if len(events) < limit:
-                        break
             finally:
                 self.is_processing = False
 
@@ -163,7 +159,7 @@ class ApplicationServicesHandler(object):
     def query_3pe(self, kind, protocol, fields):
         services = yield self._get_services_for_3pn(protocol)
 
-        results = yield preserve_context_over_deferred(defer.DeferredList([
+        results = yield make_deferred_yieldable(defer.DeferredList([
             preserve_fn(self.appservice_api.query_3pe)(service, kind, protocol, fields)
             for service in services
         ], consumeErrors=True))
diff --git a/synapse/handlers/auth.py b/synapse/handlers/auth.py
index b00446bec0..573c9db8a1 100644
--- a/synapse/handlers/auth.py
+++ b/synapse/handlers/auth.py
@@ -13,13 +13,16 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-
 from twisted.internet import defer
 
 from ._base import BaseHandler
 from synapse.api.constants import LoginType
+from synapse.api.errors import (
+    AuthError, Codes, InteractiveAuthIncompleteError, LoginError, StoreError,
+    SynapseError,
+)
+from synapse.module_api import ModuleApi
 from synapse.types import UserID
-from synapse.api.errors import AuthError, LoginError, Codes, StoreError, SynapseError
 from synapse.util.async import run_on_reactor
 from synapse.util.caches.expiringcache import ExpiringCache
 
@@ -46,7 +49,6 @@ class AuthHandler(BaseHandler):
         """
         super(AuthHandler, self).__init__(hs)
         self.checkers = {
-            LoginType.PASSWORD: self._check_password_auth,
             LoginType.RECAPTCHA: self._check_recaptcha,
             LoginType.EMAIL_IDENTITY: self._check_email_identity,
             LoginType.MSISDN: self._check_msisdn,
@@ -63,10 +65,7 @@ class AuthHandler(BaseHandler):
             reset_expiry_on_get=True,
         )
 
-        account_handler = _AccountHandler(
-            hs, check_user_exists=self.check_user_exists
-        )
-
+        account_handler = ModuleApi(hs, self)
         self.password_providers = [
             module(config=config, account_handler=account_handler)
             for module, config in hs.config.password_providers
@@ -75,39 +74,120 @@ class AuthHandler(BaseHandler):
         logger.info("Extra password_providers: %r", self.password_providers)
 
         self.hs = hs  # FIXME better possibility to access registrationHandler later?
-        self.device_handler = hs.get_device_handler()
         self.macaroon_gen = hs.get_macaroon_generator()
+        self._password_enabled = hs.config.password_enabled
+
+        # we keep this as a list despite the O(N^2) implication so that we can
+        # keep PASSWORD first and avoid confusing clients which pick the first
+        # type in the list. (NB that the spec doesn't require us to do so and
+        # clients which favour types that they don't understand over those that
+        # they do are technically broken)
+        login_types = []
+        if self._password_enabled:
+            login_types.append(LoginType.PASSWORD)
+        for provider in self.password_providers:
+            if hasattr(provider, "get_supported_login_types"):
+                for t in provider.get_supported_login_types().keys():
+                    if t not in login_types:
+                        login_types.append(t)
+        self._supported_login_types = login_types
+
+    @defer.inlineCallbacks
+    def validate_user_via_ui_auth(self, requester, request_body, clientip):
+        """
+        Checks that the user is who they claim to be, via a UI auth.
+
+        This is used for things like device deletion and password reset where
+        the user already has a valid access token, but we want to double-check
+        that it isn't stolen by re-authenticating them.
+
+        Args:
+            requester (Requester): The user, as given by the access token
+
+            request_body (dict): The body of the request sent by the client
+
+            clientip (str): The IP address of the client.
+
+        Returns:
+            defer.Deferred[dict]: the parameters for this request (which may
+                have been given only in a previous call).
+
+        Raises:
+            InteractiveAuthIncompleteError if the client has not yet completed
+                any of the permitted login flows
+
+            AuthError if the client has completed a login flow, and it gives
+                a different user to `requester`
+        """
+
+        # build a list of supported flows
+        flows = [
+            [login_type] for login_type in self._supported_login_types
+        ]
+
+        result, params, _ = yield self.check_auth(
+            flows, request_body, clientip,
+        )
+
+        # find the completed login type
+        for login_type in self._supported_login_types:
+            if login_type not in result:
+                continue
+
+            user_id = result[login_type]
+            break
+        else:
+            # this can't happen
+            raise Exception(
+                "check_auth returned True but no successful login type",
+            )
+
+        # check that the UI auth matched the access token
+        if user_id != requester.user.to_string():
+            raise AuthError(403, "Invalid auth")
+
+        defer.returnValue(params)
 
     @defer.inlineCallbacks
     def check_auth(self, flows, clientdict, clientip):
         """
         Takes a dictionary sent by the client in the login / registration
-        protocol and handles the login flow.
+        protocol and handles the User-Interactive Auth flow.
 
         As a side effect, this function fills in the 'creds' key on the user's
         session with a map, which maps each auth-type (str) to the relevant
         identity authenticated by that auth-type (mostly str, but for captcha, bool).
 
+        If no auth flows have been completed successfully, raises an
+        InteractiveAuthIncompleteError. To handle this, you can use
+        synapse.rest.client.v2_alpha._base.interactive_auth_handler as a
+        decorator.
+
         Args:
             flows (list): A list of login flows. Each flow is an ordered list of
                           strings representing auth-types. At least one full
                           flow must be completed in order for auth to be successful.
+
             clientdict: The dictionary from the client root level, not the
                         'auth' key: this method prompts for auth if none is sent.
+
             clientip (str): The IP address of the client.
+
         Returns:
-            A tuple of (authed, dict, dict, session_id) where authed is true if
-            the client has successfully completed an auth flow. If it is true
-            the first dict contains the authenticated credentials of each stage.
+            defer.Deferred[dict, dict, str]: a deferred tuple of
+                (creds, params, session_id).
+
+                'creds' contains the authenticated credentials of each stage.
 
-            If authed is false, the first dictionary is the server response to
-            the login request and should be passed back to the client.
+                'params' contains the parameters for this request (which may
+                have been given only in a previous call).
 
-            In either case, the second dict contains the parameters for this
-            request (which may have been given only in a previous call).
+                'session_id' is the ID of this session, either passed in by the
+                client or assigned by this call
 
-            session_id is the ID of this session, either passed in by the client
-            or assigned by the call to check_auth
+        Raises:
+            InteractiveAuthIncompleteError if the client has not yet completed
+                all the stages in any of the permitted flows.
         """
 
         authdict = None
@@ -135,11 +215,8 @@ class AuthHandler(BaseHandler):
             clientdict = session['clientdict']
 
         if not authdict:
-            defer.returnValue(
-                (
-                    False, self._auth_dict_for_flows(flows, session),
-                    clientdict, session['id']
-                )
+            raise InteractiveAuthIncompleteError(
+                self._auth_dict_for_flows(flows, session),
             )
 
         if 'creds' not in session:
@@ -150,14 +227,12 @@ class AuthHandler(BaseHandler):
         errordict = {}
         if 'type' in authdict:
             login_type = authdict['type']
-            if login_type not in self.checkers:
-                raise LoginError(400, "", Codes.UNRECOGNIZED)
             try:
-                result = yield self.checkers[login_type](authdict, clientip)
+                result = yield self._check_auth_dict(authdict, clientip)
                 if result:
                     creds[login_type] = result
                     self._save_session(session)
-            except LoginError, e:
+            except LoginError as e:
                 if login_type == LoginType.EMAIL_IDENTITY:
                     # riot used to have a bug where it would request a new
                     # validation token (thus sending a new email) each time it
@@ -166,7 +241,7 @@ class AuthHandler(BaseHandler):
                     #
                     # Grandfather in the old behaviour for now to avoid
                     # breaking old riot deployments.
-                    raise e
+                    raise
 
                 # this step failed. Merge the error dict into the response
                 # so that the client can have another go.
@@ -183,12 +258,14 @@ class AuthHandler(BaseHandler):
                     "Auth completed with creds: %r. Client dict has keys: %r",
                     creds, clientdict.keys()
                 )
-                defer.returnValue((True, creds, clientdict, session['id']))
+                defer.returnValue((creds, clientdict, session['id']))
 
         ret = self._auth_dict_for_flows(flows, session)
         ret['completed'] = creds.keys()
         ret.update(errordict)
-        defer.returnValue((False, ret, clientdict, session['id']))
+        raise InteractiveAuthIncompleteError(
+            ret,
+        )
 
     @defer.inlineCallbacks
     def add_oob_auth(self, stagetype, authdict, clientip):
@@ -260,16 +337,37 @@ class AuthHandler(BaseHandler):
         sess = self._get_session_info(session_id)
         return sess.setdefault('serverdict', {}).get(key, default)
 
-    def _check_password_auth(self, authdict, _):
-        if "user" not in authdict or "password" not in authdict:
-            raise LoginError(400, "", Codes.MISSING_PARAM)
+    @defer.inlineCallbacks
+    def _check_auth_dict(self, authdict, clientip):
+        """Attempt to validate the auth dict provided by a client
 
-        user_id = authdict["user"]
-        password = authdict["password"]
-        if not user_id.startswith('@'):
-            user_id = UserID.create(user_id, self.hs.hostname).to_string()
+        Args:
+            authdict (object): auth dict provided by the client
+            clientip (str): IP address of the client
 
-        return self._check_password(user_id, password)
+        Returns:
+            Deferred: result of the stage verification.
+
+        Raises:
+            StoreError if there was a problem accessing the database
+            SynapseError if there was a problem with the request
+            LoginError if there was an authentication problem.
+        """
+        login_type = authdict['type']
+        checker = self.checkers.get(login_type)
+        if checker is not None:
+            res = yield checker(authdict, clientip)
+            defer.returnValue(res)
+
+        # build a v1-login-style dict out of the authdict and fall back to the
+        # v1 code
+        user_id = authdict.get("user")
+
+        if user_id is None:
+            raise SynapseError(400, "", Codes.MISSING_PARAM)
+
+        (canonical_id, callback) = yield self.validate_login(user_id, authdict)
+        defer.returnValue(canonical_id)
 
     @defer.inlineCallbacks
     def _check_recaptcha(self, authdict, clientip):
@@ -398,26 +496,8 @@ class AuthHandler(BaseHandler):
 
         return self.sessions[session_id]
 
-    def validate_password_login(self, user_id, password):
-        """
-        Authenticates the user with their username and password.
-
-        Used only by the v1 login API.
-
-        Args:
-            user_id (str): complete @user:id
-            password (str): Password
-        Returns:
-            defer.Deferred: (str) canonical user id
-        Raises:
-            StoreError if there was a problem accessing the database
-            LoginError if there was an authentication problem.
-        """
-        return self._check_password(user_id, password)
-
     @defer.inlineCallbacks
-    def get_access_token_for_user_id(self, user_id, device_id=None,
-                                     initial_display_name=None):
+    def get_access_token_for_user_id(self, user_id, device_id=None):
         """
         Creates a new access token for the user with the given user ID.
 
@@ -431,13 +511,10 @@ class AuthHandler(BaseHandler):
             device_id (str|None): the device ID to associate with the tokens.
                None to leave the tokens unassociated with a device (deprecated:
                we should always have a device ID)
-            initial_display_name (str): display name to associate with the
-               device if it needs re-registering
         Returns:
               The access token for the user's session.
         Raises:
             StoreError if there was a problem storing the token.
-            LoginError if there was an authentication problem.
         """
         logger.info("Logging in user %s on device %s", user_id, device_id)
         access_token = yield self.issue_access_token(user_id, device_id)
@@ -447,9 +524,11 @@ class AuthHandler(BaseHandler):
         # really don't want is active access_tokens without a record of the
         # device, so we double-check it here.
         if device_id is not None:
-            yield self.device_handler.check_device_registered(
-                user_id, device_id, initial_display_name
-            )
+            try:
+                yield self.store.get_device(user_id, device_id)
+            except StoreError:
+                yield self.store.delete_access_token(access_token)
+                raise StoreError(400, "Login raced against device deletion")
 
         defer.returnValue(access_token)
 
@@ -501,29 +580,115 @@ class AuthHandler(BaseHandler):
             )
         defer.returnValue(result)
 
+    def get_supported_login_types(self):
+        """Get a the login types supported for the /login API
+
+        By default this is just 'm.login.password' (unless password_enabled is
+        False in the config file), but password auth providers can provide
+        other login types.
+
+        Returns:
+            Iterable[str]: login types
+        """
+        return self._supported_login_types
+
     @defer.inlineCallbacks
-    def _check_password(self, user_id, password):
-        """Authenticate a user against the LDAP and local databases.
+    def validate_login(self, username, login_submission):
+        """Authenticates the user for the /login API
 
-        user_id is checked case insensitively against the local database, but
-        will throw if there are multiple inexact matches.
+        Also used by the user-interactive auth flow to validate
+        m.login.password auth types.
 
         Args:
-            user_id (str): complete @user:id
+            username (str): username supplied by the user
+            login_submission (dict): the whole of the login submission
+                (including 'type' and other relevant fields)
         Returns:
-            (str) the canonical_user_id
+            Deferred[str, func]: canonical user id, and optional callback
+                to be called once the access token and device id are issued
         Raises:
-            LoginError if login fails
+            StoreError if there was a problem accessing the database
+            SynapseError if there was a problem with the request
+            LoginError if there was an authentication problem.
         """
+
+        if username.startswith('@'):
+            qualified_user_id = username
+        else:
+            qualified_user_id = UserID(
+                username, self.hs.hostname
+            ).to_string()
+
+        login_type = login_submission.get("type")
+        known_login_type = False
+
+        # special case to check for "password" for the check_password interface
+        # for the auth providers
+        password = login_submission.get("password")
+        if login_type == LoginType.PASSWORD:
+            if not self._password_enabled:
+                raise SynapseError(400, "Password login has been disabled.")
+            if not password:
+                raise SynapseError(400, "Missing parameter: password")
+
         for provider in self.password_providers:
-            is_valid = yield provider.check_password(user_id, password)
-            if is_valid:
-                defer.returnValue(user_id)
+            if (hasattr(provider, "check_password")
+                    and login_type == LoginType.PASSWORD):
+                known_login_type = True
+                is_valid = yield provider.check_password(
+                    qualified_user_id, password,
+                )
+                if is_valid:
+                    defer.returnValue((qualified_user_id, None))
+
+            if (not hasattr(provider, "get_supported_login_types")
+                    or not hasattr(provider, "check_auth")):
+                # this password provider doesn't understand custom login types
+                continue
+
+            supported_login_types = provider.get_supported_login_types()
+            if login_type not in supported_login_types:
+                # this password provider doesn't understand this login type
+                continue
+
+            known_login_type = True
+            login_fields = supported_login_types[login_type]
+
+            missing_fields = []
+            login_dict = {}
+            for f in login_fields:
+                if f not in login_submission:
+                    missing_fields.append(f)
+                else:
+                    login_dict[f] = login_submission[f]
+            if missing_fields:
+                raise SynapseError(
+                    400, "Missing parameters for login type %s: %s" % (
+                        login_type,
+                        missing_fields,
+                    ),
+                )
 
-        canonical_user_id = yield self._check_local_password(user_id, password)
+            result = yield provider.check_auth(
+                username, login_type, login_dict,
+            )
+            if result:
+                if isinstance(result, str):
+                    result = (result, None)
+                defer.returnValue(result)
+
+        if login_type == LoginType.PASSWORD:
+            known_login_type = True
+
+            canonical_user_id = yield self._check_local_password(
+                qualified_user_id, password,
+            )
 
-        if canonical_user_id:
-            defer.returnValue(canonical_user_id)
+            if canonical_user_id:
+                defer.returnValue((canonical_user_id, None))
+
+        if not known_login_type:
+            raise SynapseError(400, "Unknown login type %s" % login_type)
 
         # unknown username or invalid password. We raise a 403 here, but note
         # that if we're doing user-interactive login, it turns all LoginErrors
@@ -573,22 +738,65 @@ class AuthHandler(BaseHandler):
             raise AuthError(403, "Invalid token", errcode=Codes.FORBIDDEN)
 
     @defer.inlineCallbacks
-    def set_password(self, user_id, newpassword, requester=None):
-        password_hash = self.hash(newpassword)
+    def delete_access_token(self, access_token):
+        """Invalidate a single access token
 
-        except_access_token_id = requester.access_token_id if requester else None
+        Args:
+            access_token (str): access token to be deleted
 
-        try:
-            yield self.store.user_set_password_hash(user_id, password_hash)
-        except StoreError as e:
-            if e.code == 404:
-                raise SynapseError(404, "Unknown user", Codes.NOT_FOUND)
-            raise e
-        yield self.store.user_delete_access_tokens(
-            user_id, except_access_token_id
+        Returns:
+            Deferred
+        """
+        user_info = yield self.auth.get_user_by_access_token(access_token)
+        yield self.store.delete_access_token(access_token)
+
+        # see if any of our auth providers want to know about this
+        for provider in self.password_providers:
+            if hasattr(provider, "on_logged_out"):
+                yield provider.on_logged_out(
+                    user_id=str(user_info["user"]),
+                    device_id=user_info["device_id"],
+                    access_token=access_token,
+                )
+
+        # delete pushers associated with this access token
+        if user_info["token_id"] is not None:
+            yield self.hs.get_pusherpool().remove_pushers_by_access_token(
+                str(user_info["user"]), (user_info["token_id"], )
+            )
+
+    @defer.inlineCallbacks
+    def delete_access_tokens_for_user(self, user_id, except_token_id=None,
+                                      device_id=None):
+        """Invalidate access tokens belonging to a user
+
+        Args:
+            user_id (str):  ID of user the tokens belong to
+            except_token_id (str|None): access_token ID which should *not* be
+                deleted
+            device_id (str|None):  ID of device the tokens are associated with.
+                If None, tokens associated with any device (or no device) will
+                be deleted
+        Returns:
+            Deferred
+        """
+        tokens_and_devices = yield self.store.user_delete_access_tokens(
+            user_id, except_token_id=except_token_id, device_id=device_id,
         )
-        yield self.hs.get_pusherpool().remove_pushers_by_user(
-            user_id, except_access_token_id
+
+        # see if any of our auth providers want to know about this
+        for provider in self.password_providers:
+            if hasattr(provider, "on_logged_out"):
+                for token, token_id, device_id in tokens_and_devices:
+                    yield provider.on_logged_out(
+                        user_id=user_id,
+                        device_id=device_id,
+                        access_token=token,
+                    )
+
+        # delete pushers associated with the access tokens
+        yield self.hs.get_pusherpool().remove_pushers_by_access_token(
+            user_id, (token_id for _, token_id, _ in tokens_and_devices),
         )
 
     @defer.inlineCallbacks
@@ -696,30 +904,3 @@ class MacaroonGeneartor(object):
         macaroon.add_first_party_caveat("gen = 1")
         macaroon.add_first_party_caveat("user_id = %s" % (user_id,))
         return macaroon
-
-
-class _AccountHandler(object):
-    """A proxy object that gets passed to password auth providers so they
-    can register new users etc if necessary.
-    """
-    def __init__(self, hs, check_user_exists):
-        self.hs = hs
-
-        self._check_user_exists = check_user_exists
-
-    def check_user_exists(self, user_id):
-        """Check if user exissts.
-
-        Returns:
-            Deferred(bool)
-        """
-        return self._check_user_exists(user_id)
-
-    def register(self, localpart):
-        """Registers a new user with given localpart
-
-        Returns:
-            Deferred: a 2-tuple of (user_id, access_token)
-        """
-        reg = self.hs.get_handlers().registration_handler
-        return reg.register(localpart=localpart)
diff --git a/synapse/handlers/deactivate_account.py b/synapse/handlers/deactivate_account.py
new file mode 100644
index 0000000000..b1d3814909
--- /dev/null
+++ b/synapse/handlers/deactivate_account.py
@@ -0,0 +1,52 @@
+# -*- coding: utf-8 -*-
+# Copyright 2017 New Vector Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+from twisted.internet import defer
+
+from ._base import BaseHandler
+
+import logging
+
+logger = logging.getLogger(__name__)
+
+
+class DeactivateAccountHandler(BaseHandler):
+    """Handler which deals with deactivating user accounts."""
+    def __init__(self, hs):
+        super(DeactivateAccountHandler, self).__init__(hs)
+        self._auth_handler = hs.get_auth_handler()
+        self._device_handler = hs.get_device_handler()
+
+    @defer.inlineCallbacks
+    def deactivate_account(self, user_id):
+        """Deactivate a user's account
+
+        Args:
+            user_id (str): ID of user to be deactivated
+
+        Returns:
+            Deferred
+        """
+        # FIXME: Theoretically there is a race here wherein user resets
+        # password using threepid.
+
+        # first delete any devices belonging to the user, which will also
+        # delete corresponding access tokens.
+        yield self._device_handler.delete_all_devices_for_user(user_id)
+        # then delete any remaining access tokens which weren't associated with
+        # a device.
+        yield self._auth_handler.delete_access_tokens_for_user(user_id)
+
+        yield self.store.user_delete_threepids(user_id)
+        yield self.store.user_set_password_hash(user_id, None)
diff --git a/synapse/handlers/device.py b/synapse/handlers/device.py
index dac4b3f4e0..2152efc692 100644
--- a/synapse/handlers/device.py
+++ b/synapse/handlers/device.py
@@ -34,6 +34,7 @@ class DeviceHandler(BaseHandler):
 
         self.hs = hs
         self.state = hs.get_state_handler()
+        self._auth_handler = hs.get_auth_handler()
         self.federation_sender = hs.get_federation_sender()
         self.federation = hs.get_replication_layer()
 
@@ -159,9 +160,8 @@ class DeviceHandler(BaseHandler):
             else:
                 raise
 
-        yield self.store.user_delete_access_tokens(
+        yield self._auth_handler.delete_access_tokens_for_user(
             user_id, device_id=device_id,
-            delete_refresh_tokens=True,
         )
 
         yield self.store.delete_e2e_keys_by_device(
@@ -171,12 +171,30 @@ class DeviceHandler(BaseHandler):
         yield self.notify_device_update(user_id, [device_id])
 
     @defer.inlineCallbacks
+    def delete_all_devices_for_user(self, user_id, except_device_id=None):
+        """Delete all of the user's devices
+
+        Args:
+            user_id (str):
+            except_device_id (str|None): optional device id which should not
+                be deleted
+
+        Returns:
+            defer.Deferred:
+        """
+        device_map = yield self.store.get_devices_by_user(user_id)
+        device_ids = device_map.keys()
+        if except_device_id is not None:
+            device_ids = [d for d in device_ids if d != except_device_id]
+        yield self.delete_devices(user_id, device_ids)
+
+    @defer.inlineCallbacks
     def delete_devices(self, user_id, device_ids):
         """ Delete several devices
 
         Args:
             user_id (str):
-            device_ids (str): The list of device IDs to delete
+            device_ids (List[str]): The list of device IDs to delete
 
         Returns:
             defer.Deferred:
@@ -194,9 +212,8 @@ class DeviceHandler(BaseHandler):
         # Delete access tokens and e2e keys for each device. Not optimised as it is not
         # considered as part of a critical path.
         for device_id in device_ids:
-            yield self.store.user_delete_access_tokens(
+            yield self._auth_handler.delete_access_tokens_for_user(
                 user_id, device_id=device_id,
-                delete_refresh_tokens=True,
             )
             yield self.store.delete_e2e_keys_by_device(
                 user_id=user_id, device_id=device_id
diff --git a/synapse/handlers/directory.py b/synapse/handlers/directory.py
index 943554ce98..a0464ae5c0 100644
--- a/synapse/handlers/directory.py
+++ b/synapse/handlers/directory.py
@@ -40,6 +40,8 @@ class DirectoryHandler(BaseHandler):
             "directory", self.on_directory_query
         )
 
+        self.spam_checker = hs.get_spam_checker()
+
     @defer.inlineCallbacks
     def _create_association(self, room_alias, room_id, servers=None, creator=None):
         # general association creation for both human users and app services
@@ -73,6 +75,11 @@ class DirectoryHandler(BaseHandler):
         # association creation for human users
         # TODO(erikj): Do user auth.
 
+        if not self.spam_checker.user_may_create_room_alias(user_id, room_alias):
+            raise SynapseError(
+                403, "This user is not permitted to create this alias",
+            )
+
         can_create = yield self.can_modify_alias(
             room_alias,
             user_id=user_id
@@ -327,6 +334,14 @@ class DirectoryHandler(BaseHandler):
         room_id (str)
         visibility (str): "public" or "private"
         """
+        if not self.spam_checker.user_may_publish_room(
+            requester.user.to_string(), room_id
+        ):
+            raise AuthError(
+                403,
+                "This user is not permitted to publish rooms to the room list"
+            )
+
         if requester.is_guest:
             raise AuthError(403, "Guests cannot edit the published room list")
 
diff --git a/synapse/handlers/federation.py b/synapse/handlers/federation.py
index 18f87cad67..ac70730885 100644
--- a/synapse/handlers/federation.py
+++ b/synapse/handlers/federation.py
@@ -14,7 +14,6 @@
 # limitations under the License.
 
 """Contains handlers for federation events."""
-import synapse.util.logcontext
 from signedjson.key import decode_verify_key_bytes
 from signedjson.sign import verify_signed_json
 from unpaddedbase64 import decode_base64
@@ -26,10 +25,7 @@ from synapse.api.errors import (
 )
 from synapse.api.constants import EventTypes, Membership, RejectedReason
 from synapse.events.validator import EventValidator
-from synapse.util import unwrapFirstError
-from synapse.util.logcontext import (
-    preserve_fn, preserve_context_over_deferred
-)
+from synapse.util import unwrapFirstError, logcontext
 from synapse.util.metrics import measure_func
 from synapse.util.logutils import log_function
 from synapse.util.async import run_on_reactor, Linearizer
@@ -77,6 +73,7 @@ class FederationHandler(BaseHandler):
         self.action_generator = hs.get_action_generator()
         self.is_mine_id = hs.is_mine_id
         self.pusher_pool = hs.get_pusherpool()
+        self.spam_checker = hs.get_spam_checker()
 
         self.replication_layer.set_handler(self)
 
@@ -125,6 +122,28 @@ class FederationHandler(BaseHandler):
             self.room_queues[pdu.room_id].append((pdu, origin))
             return
 
+        # If we're no longer in the room just ditch the event entirely. This
+        # is probably an old server that has come back and thinks we're still
+        # in the room (or we've been rejoined to the room by a state reset).
+        #
+        # If we were never in the room then maybe our database got vaped and
+        # we should check if we *are* in fact in the room. If we are then we
+        # can magically rejoin the room.
+        is_in_room = yield self.auth.check_host_in_room(
+            pdu.room_id,
+            self.server_name
+        )
+        if not is_in_room:
+            was_in_room = yield self.store.was_host_joined(
+                pdu.room_id, self.server_name,
+            )
+            if was_in_room:
+                logger.info(
+                    "Ignoring PDU %s for room %s from %s as we've left the room!",
+                    pdu.event_id, pdu.room_id, origin,
+                )
+                return
+
         state = None
 
         auth_chain = []
@@ -208,7 +227,7 @@ class FederationHandler(BaseHandler):
                 state, auth_chain = yield self.replication_layer.get_state_for_room(
                     origin, pdu.room_id, pdu.event_id,
                 )
-            except:
+            except Exception:
                 logger.exception("Failed to get state for event: %s", pdu.event_id)
 
         yield self._process_received_pdu(
@@ -442,7 +461,7 @@ class FederationHandler(BaseHandler):
         def check_match(id):
             try:
                 return server_name == get_domain_from_id(id)
-            except:
+            except Exception:
                 return False
 
         # Parses mapping `event_id -> (type, state_key) -> state event_id`
@@ -480,7 +499,7 @@ class FederationHandler(BaseHandler):
                             continue
                         try:
                             domain = get_domain_from_id(ev.state_key)
-                        except:
+                        except Exception:
                             continue
 
                         if domain != server_name:
@@ -591,9 +610,9 @@ class FederationHandler(BaseHandler):
                     missing_auth - failed_to_fetch
                 )
 
-                results = yield preserve_context_over_deferred(defer.gatherResults(
+                results = yield logcontext.make_deferred_yieldable(defer.gatherResults(
                     [
-                        preserve_fn(self.replication_layer.get_pdu)(
+                        logcontext.preserve_fn(self.replication_layer.get_pdu)(
                             [dest],
                             event_id,
                             outlier=True,
@@ -719,7 +738,7 @@ class FederationHandler(BaseHandler):
                         joined_domains[dom] = min(d, old_d)
                     else:
                         joined_domains[dom] = d
-                except:
+                except Exception:
                     pass
 
             return sorted(joined_domains.items(), key=lambda d: d[1])
@@ -785,10 +804,14 @@ class FederationHandler(BaseHandler):
         event_ids = list(extremities.keys())
 
         logger.debug("calling resolve_state_groups in _maybe_backfill")
-        states = yield preserve_context_over_deferred(defer.gatherResults([
-            preserve_fn(self.state_handler.resolve_state_groups)(room_id, [e])
-            for e in event_ids
-        ]))
+        states = yield logcontext.make_deferred_yieldable(defer.gatherResults(
+            [
+                logcontext.preserve_fn(self.state_handler.resolve_state_groups)(
+                    room_id, [e]
+                )
+                for e in event_ids
+            ], consumeErrors=True,
+        ))
         states = dict(zip(event_ids, [s.state for s in states]))
 
         state_map = yield self.store.get_events(
@@ -917,7 +940,7 @@ class FederationHandler(BaseHandler):
                     room_creator_user_id="",
                     is_public=False
                 )
-            except:
+            except Exception:
                 # FIXME
                 pass
 
@@ -941,9 +964,7 @@ class FederationHandler(BaseHandler):
             # lots of requests for missing prev_events which we do actually
             # have. Hence we fire off the deferred, but don't wait for it.
 
-            synapse.util.logcontext.preserve_fn(self._handle_queued_pdus)(
-                room_queue
-            )
+            logcontext.preserve_fn(self._handle_queued_pdus)(room_queue)
 
         defer.returnValue(True)
 
@@ -1070,6 +1091,9 @@ class FederationHandler(BaseHandler):
         """
         event = pdu
 
+        if event.state_key is None:
+            raise SynapseError(400, "The invite event did not have a state key")
+
         is_blocked = yield self.store.is_room_blocked(event.room_id)
         if is_blocked:
             raise SynapseError(403, "This room has been blocked on this server")
@@ -1077,6 +1101,13 @@ class FederationHandler(BaseHandler):
         if self.hs.config.block_non_admin_invites:
             raise SynapseError(403, "This server does not accept room invites")
 
+        if not self.spam_checker.user_may_invite(
+            event.sender, event.state_key, event.room_id,
+        ):
+            raise SynapseError(
+                403, "This user is not permitted to send invites to this server/user"
+            )
+
         membership = event.content.get("membership")
         if event.type != EventTypes.Member or membership != Membership.INVITE:
             raise SynapseError(400, "The event was not an m.room.member invite event")
@@ -1085,9 +1116,6 @@ class FederationHandler(BaseHandler):
         if sender_domain != origin:
             raise SynapseError(400, "The invite event was not from the server sending it")
 
-        if event.state_key is None:
-            raise SynapseError(400, "The invite event did not have a state key")
-
         if not self.is_mine_id(event.state_key):
             raise SynapseError(400, "The invite event must be for this server")
 
@@ -1430,7 +1458,7 @@ class FederationHandler(BaseHandler):
         if not backfilled:
             # this intentionally does not yield: we don't care about the result
             # and don't need to wait for it.
-            preserve_fn(self.pusher_pool.on_new_notifications)(
+            logcontext.preserve_fn(self.pusher_pool.on_new_notifications)(
                 event_stream_id, max_stream_id
             )
 
@@ -1443,16 +1471,16 @@ class FederationHandler(BaseHandler):
         a bunch of outliers, but not a chunk of individual events that depend
         on each other for state calculations.
         """
-        contexts = yield preserve_context_over_deferred(defer.gatherResults(
+        contexts = yield logcontext.make_deferred_yieldable(defer.gatherResults(
             [
-                preserve_fn(self._prep_event)(
+                logcontext.preserve_fn(self._prep_event)(
                     origin,
                     ev_info["event"],
                     state=ev_info.get("state"),
                     auth_events=ev_info.get("auth_events"),
                 )
                 for ev_info in event_infos
-            ]
+            ], consumeErrors=True,
         ))
 
         yield self.store.persist_events(
@@ -1678,6 +1706,17 @@ class FederationHandler(BaseHandler):
     @defer.inlineCallbacks
     @log_function
     def do_auth(self, origin, event, context, auth_events):
+        """
+
+        Args:
+            origin (str):
+            event (synapse.events.FrozenEvent):
+            context (synapse.events.snapshot.EventContext):
+            auth_events (dict[(str, str)->str]):
+
+        Returns:
+            defer.Deferred[None]
+        """
         # Check if we have all the auth events.
         current_state = set(e.event_id for e in auth_events.values())
         event_auth_events = set(e_id for e_id, _ in event.auth_events)
@@ -1747,7 +1786,7 @@ class FederationHandler(BaseHandler):
                     [e_id for e_id, _ in event.auth_events]
                 )
                 seen_events = set(have_events.keys())
-            except:
+            except Exception:
                 # FIXME:
                 logger.exception("Failed to get auth chain")
 
@@ -1760,18 +1799,17 @@ class FederationHandler(BaseHandler):
             # Do auth conflict res.
             logger.info("Different auth: %s", different_auth)
 
-            different_events = yield preserve_context_over_deferred(defer.gatherResults(
-                [
-                    preserve_fn(self.store.get_event)(
+            different_events = yield logcontext.make_deferred_yieldable(
+                defer.gatherResults([
+                    logcontext.preserve_fn(self.store.get_event)(
                         d,
                         allow_none=True,
                         allow_rejected=False,
                     )
                     for d in different_auth
                     if d in have_events and not have_events[d]
-                ],
-                consumeErrors=True
-            )).addErrback(unwrapFirstError)
+                ], consumeErrors=True)
+            ).addErrback(unwrapFirstError)
 
             if different_events:
                 local_view = dict(auth_events)
@@ -1790,16 +1828,9 @@ class FederationHandler(BaseHandler):
                 current_state = set(e.event_id for e in auth_events.values())
                 different_auth = event_auth_events - current_state
 
-                context.current_state_ids = dict(context.current_state_ids)
-                context.current_state_ids.update({
-                    k: a.event_id for k, a in auth_events.items()
-                    if k != event_key
-                })
-                context.prev_state_ids = dict(context.prev_state_ids)
-                context.prev_state_ids.update({
-                    k: a.event_id for k, a in auth_events.items()
-                })
-                context.state_group = self.store.get_next_state_group()
+                self._update_context_for_auth_events(
+                    context, auth_events, event_key,
+                )
 
         if different_auth and not event.internal_metadata.is_outlier():
             logger.info("Different auth after resolution: %s", different_auth)
@@ -1872,23 +1903,16 @@ class FederationHandler(BaseHandler):
                         except AuthError:
                             pass
 
-                except:
+                except Exception:
                     # FIXME:
                     logger.exception("Failed to query auth chain")
 
                 # 4. Look at rejects and their proofs.
                 # TODO.
 
-                context.current_state_ids = dict(context.current_state_ids)
-                context.current_state_ids.update({
-                    k: a.event_id for k, a in auth_events.items()
-                    if k != event_key
-                })
-                context.prev_state_ids = dict(context.prev_state_ids)
-                context.prev_state_ids.update({
-                    k: a.event_id for k, a in auth_events.items()
-                })
-                context.state_group = self.store.get_next_state_group()
+                self._update_context_for_auth_events(
+                    context, auth_events, event_key,
+                )
 
         try:
             self.auth.check(event, auth_events=auth_events)
@@ -1896,6 +1920,35 @@ class FederationHandler(BaseHandler):
             logger.warn("Failed auth resolution for %r because %s", event, e)
             raise e
 
+    def _update_context_for_auth_events(self, context, auth_events,
+                                        event_key):
+        """Update the state_ids in an event context after auth event resolution
+
+        Args:
+            context (synapse.events.snapshot.EventContext): event context
+                to be updated
+
+            auth_events (dict[(str, str)->str]): Events to update in the event
+                context.
+
+            event_key ((str, str)): (type, state_key) for the current event.
+                this will not be included in the current_state in the context.
+        """
+        state_updates = {
+            k: a.event_id for k, a in auth_events.iteritems()
+            if k != event_key
+        }
+        context.current_state_ids = dict(context.current_state_ids)
+        context.current_state_ids.update(state_updates)
+        if context.delta_ids is not None:
+            context.delta_ids = dict(context.delta_ids)
+            context.delta_ids.update(state_updates)
+        context.prev_state_ids = dict(context.prev_state_ids)
+        context.prev_state_ids.update({
+            k: a.event_id for k, a in auth_events.iteritems()
+        })
+        context.state_group = self.store.get_next_state_group()
+
     @defer.inlineCallbacks
     def construct_auth_difference(self, local_auth, remote_auth):
         """ Given a local and remote auth chain, find the differences. This
@@ -1939,7 +1992,7 @@ class FederationHandler(BaseHandler):
         def get_next(it, opt=None):
             try:
                 return it.next()
-            except:
+            except Exception:
                 return opt
 
         current_local = get_next(local_iter)
diff --git a/synapse/handlers/groups_local.py b/synapse/handlers/groups_local.py
new file mode 100644
index 0000000000..7e5d3f148d
--- /dev/null
+++ b/synapse/handlers/groups_local.py
@@ -0,0 +1,429 @@
+# -*- coding: utf-8 -*-
+# Copyright 2017 Vector Creations Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from twisted.internet import defer
+
+from synapse.api.errors import SynapseError
+from synapse.types import get_domain_from_id
+
+import logging
+
+logger = logging.getLogger(__name__)
+
+
+def _create_rerouter(func_name):
+    """Returns a function that looks at the group id and calls the function
+    on federation or the local group server if the group is local
+    """
+    def f(self, group_id, *args, **kwargs):
+        if self.is_mine_id(group_id):
+            return getattr(self.groups_server_handler, func_name)(
+                group_id, *args, **kwargs
+            )
+        else:
+            destination = get_domain_from_id(group_id)
+            return getattr(self.transport_client, func_name)(
+                destination, group_id, *args, **kwargs
+            )
+    return f
+
+
+class GroupsLocalHandler(object):
+    def __init__(self, hs):
+        self.hs = hs
+        self.store = hs.get_datastore()
+        self.room_list_handler = hs.get_room_list_handler()
+        self.groups_server_handler = hs.get_groups_server_handler()
+        self.transport_client = hs.get_federation_transport_client()
+        self.auth = hs.get_auth()
+        self.clock = hs.get_clock()
+        self.keyring = hs.get_keyring()
+        self.is_mine_id = hs.is_mine_id
+        self.signing_key = hs.config.signing_key[0]
+        self.server_name = hs.hostname
+        self.notifier = hs.get_notifier()
+        self.attestations = hs.get_groups_attestation_signing()
+
+        self.profile_handler = hs.get_profile_handler()
+
+        # Ensure attestations get renewed
+        hs.get_groups_attestation_renewer()
+
+    # The following functions merely route the query to the local groups server
+    # or federation depending on if the group is local or remote
+
+    get_group_profile = _create_rerouter("get_group_profile")
+    update_group_profile = _create_rerouter("update_group_profile")
+    get_rooms_in_group = _create_rerouter("get_rooms_in_group")
+
+    get_invited_users_in_group = _create_rerouter("get_invited_users_in_group")
+
+    add_room_to_group = _create_rerouter("add_room_to_group")
+    update_room_in_group = _create_rerouter("update_room_in_group")
+    remove_room_from_group = _create_rerouter("remove_room_from_group")
+
+    update_group_summary_room = _create_rerouter("update_group_summary_room")
+    delete_group_summary_room = _create_rerouter("delete_group_summary_room")
+
+    update_group_category = _create_rerouter("update_group_category")
+    delete_group_category = _create_rerouter("delete_group_category")
+    get_group_category = _create_rerouter("get_group_category")
+    get_group_categories = _create_rerouter("get_group_categories")
+
+    update_group_summary_user = _create_rerouter("update_group_summary_user")
+    delete_group_summary_user = _create_rerouter("delete_group_summary_user")
+
+    update_group_role = _create_rerouter("update_group_role")
+    delete_group_role = _create_rerouter("delete_group_role")
+    get_group_role = _create_rerouter("get_group_role")
+    get_group_roles = _create_rerouter("get_group_roles")
+
+    @defer.inlineCallbacks
+    def get_group_summary(self, group_id, requester_user_id):
+        """Get the group summary for a group.
+
+        If the group is remote we check that the users have valid attestations.
+        """
+        if self.is_mine_id(group_id):
+            res = yield self.groups_server_handler.get_group_summary(
+                group_id, requester_user_id
+            )
+        else:
+            res = yield self.transport_client.get_group_summary(
+                get_domain_from_id(group_id), group_id, requester_user_id,
+            )
+
+            group_server_name = get_domain_from_id(group_id)
+
+            # Loop through the users and validate the attestations.
+            chunk = res["users_section"]["users"]
+            valid_users = []
+            for entry in chunk:
+                g_user_id = entry["user_id"]
+                attestation = entry.pop("attestation", {})
+                try:
+                    if get_domain_from_id(g_user_id) != group_server_name:
+                        yield self.attestations.verify_attestation(
+                            attestation,
+                            group_id=group_id,
+                            user_id=g_user_id,
+                            server_name=get_domain_from_id(g_user_id),
+                        )
+                    valid_users.append(entry)
+                except Exception as e:
+                    logger.info("Failed to verify user is in group: %s", e)
+
+            res["users_section"]["users"] = valid_users
+
+            res["users_section"]["users"].sort(key=lambda e: e.get("order", 0))
+            res["rooms_section"]["rooms"].sort(key=lambda e: e.get("order", 0))
+
+        # Add `is_publicised` flag to indicate whether the user has publicised their
+        # membership of the group on their profile
+        result = yield self.store.get_publicised_groups_for_user(requester_user_id)
+        is_publicised = group_id in result
+
+        res.setdefault("user", {})["is_publicised"] = is_publicised
+
+        defer.returnValue(res)
+
+    @defer.inlineCallbacks
+    def create_group(self, group_id, user_id, content):
+        """Create a group
+        """
+
+        logger.info("Asking to create group with ID: %r", group_id)
+
+        if self.is_mine_id(group_id):
+            res = yield self.groups_server_handler.create_group(
+                group_id, user_id, content
+            )
+            local_attestation = None
+            remote_attestation = None
+        else:
+            local_attestation = self.attestations.create_attestation(group_id, user_id)
+            content["attestation"] = local_attestation
+
+            content["user_profile"] = yield self.profile_handler.get_profile(user_id)
+
+            res = yield self.transport_client.create_group(
+                get_domain_from_id(group_id), group_id, user_id, content,
+            )
+
+            remote_attestation = res["attestation"]
+            yield self.attestations.verify_attestation(
+                remote_attestation,
+                group_id=group_id,
+                user_id=user_id,
+                server_name=get_domain_from_id(group_id),
+            )
+
+        is_publicised = content.get("publicise", False)
+        token = yield self.store.register_user_group_membership(
+            group_id, user_id,
+            membership="join",
+            is_admin=True,
+            local_attestation=local_attestation,
+            remote_attestation=remote_attestation,
+            is_publicised=is_publicised,
+        )
+        self.notifier.on_new_event(
+            "groups_key", token, users=[user_id],
+        )
+
+        defer.returnValue(res)
+
+    @defer.inlineCallbacks
+    def get_users_in_group(self, group_id, requester_user_id):
+        """Get users in a group
+        """
+        if self.is_mine_id(group_id):
+            res = yield self.groups_server_handler.get_users_in_group(
+                group_id, requester_user_id
+            )
+            defer.returnValue(res)
+
+        group_server_name = get_domain_from_id(group_id)
+
+        res = yield self.transport_client.get_users_in_group(
+            get_domain_from_id(group_id), group_id, requester_user_id,
+        )
+
+        chunk = res["chunk"]
+        valid_entries = []
+        for entry in chunk:
+            g_user_id = entry["user_id"]
+            attestation = entry.pop("attestation", {})
+            try:
+                if get_domain_from_id(g_user_id) != group_server_name:
+                    yield self.attestations.verify_attestation(
+                        attestation,
+                        group_id=group_id,
+                        user_id=g_user_id,
+                        server_name=get_domain_from_id(g_user_id),
+                    )
+                valid_entries.append(entry)
+            except Exception as e:
+                logger.info("Failed to verify user is in group: %s", e)
+
+        res["chunk"] = valid_entries
+
+        defer.returnValue(res)
+
+    @defer.inlineCallbacks
+    def join_group(self, group_id, user_id, content):
+        """Request to join a group
+        """
+        raise NotImplementedError()  # TODO
+
+    @defer.inlineCallbacks
+    def accept_invite(self, group_id, user_id, content):
+        """Accept an invite to a group
+        """
+        if self.is_mine_id(group_id):
+            yield self.groups_server_handler.accept_invite(
+                group_id, user_id, content
+            )
+            local_attestation = None
+            remote_attestation = None
+        else:
+            local_attestation = self.attestations.create_attestation(group_id, user_id)
+            content["attestation"] = local_attestation
+
+            res = yield self.transport_client.accept_group_invite(
+                get_domain_from_id(group_id), group_id, user_id, content,
+            )
+
+            remote_attestation = res["attestation"]
+
+            yield self.attestations.verify_attestation(
+                remote_attestation,
+                group_id=group_id,
+                user_id=user_id,
+                server_name=get_domain_from_id(group_id),
+            )
+
+        # TODO: Check that the group is public and we're being added publically
+        is_publicised = content.get("publicise", False)
+
+        token = yield self.store.register_user_group_membership(
+            group_id, user_id,
+            membership="join",
+            is_admin=False,
+            local_attestation=local_attestation,
+            remote_attestation=remote_attestation,
+            is_publicised=is_publicised,
+        )
+        self.notifier.on_new_event(
+            "groups_key", token, users=[user_id],
+        )
+
+        defer.returnValue({})
+
+    @defer.inlineCallbacks
+    def invite(self, group_id, user_id, requester_user_id, config):
+        """Invite a user to a group
+        """
+        content = {
+            "requester_user_id": requester_user_id,
+            "config": config,
+        }
+        if self.is_mine_id(group_id):
+            res = yield self.groups_server_handler.invite_to_group(
+                group_id, user_id, requester_user_id, content,
+            )
+        else:
+            res = yield self.transport_client.invite_to_group(
+                get_domain_from_id(group_id), group_id, user_id, requester_user_id,
+                content,
+            )
+
+        defer.returnValue(res)
+
+    @defer.inlineCallbacks
+    def on_invite(self, group_id, user_id, content):
+        """One of our users were invited to a group
+        """
+        # TODO: Support auto join and rejection
+
+        if not self.is_mine_id(user_id):
+            raise SynapseError(400, "User not on this server")
+
+        local_profile = {}
+        if "profile" in content:
+            if "name" in content["profile"]:
+                local_profile["name"] = content["profile"]["name"]
+            if "avatar_url" in content["profile"]:
+                local_profile["avatar_url"] = content["profile"]["avatar_url"]
+
+        token = yield self.store.register_user_group_membership(
+            group_id, user_id,
+            membership="invite",
+            content={"profile": local_profile, "inviter": content["inviter"]},
+        )
+        self.notifier.on_new_event(
+            "groups_key", token, users=[user_id],
+        )
+        try:
+            user_profile = yield self.profile_handler.get_profile(user_id)
+        except Exception as e:
+            logger.warn("No profile for user %s: %s", user_id, e)
+            user_profile = {}
+
+        defer.returnValue({"state": "invite", "user_profile": user_profile})
+
+    @defer.inlineCallbacks
+    def remove_user_from_group(self, group_id, user_id, requester_user_id, content):
+        """Remove a user from a group
+        """
+        if user_id == requester_user_id:
+            token = yield self.store.register_user_group_membership(
+                group_id, user_id,
+                membership="leave",
+            )
+            self.notifier.on_new_event(
+                "groups_key", token, users=[user_id],
+            )
+
+            # TODO: Should probably remember that we tried to leave so that we can
+            # retry if the group server is currently down.
+
+        if self.is_mine_id(group_id):
+            res = yield self.groups_server_handler.remove_user_from_group(
+                group_id, user_id, requester_user_id, content,
+            )
+        else:
+            content["requester_user_id"] = requester_user_id
+            res = yield self.transport_client.remove_user_from_group(
+                get_domain_from_id(group_id), group_id, requester_user_id,
+                user_id, content,
+            )
+
+        defer.returnValue(res)
+
+    @defer.inlineCallbacks
+    def user_removed_from_group(self, group_id, user_id, content):
+        """One of our users was removed/kicked from a group
+        """
+        # TODO: Check if user in group
+        token = yield self.store.register_user_group_membership(
+            group_id, user_id,
+            membership="leave",
+        )
+        self.notifier.on_new_event(
+            "groups_key", token, users=[user_id],
+        )
+
+    @defer.inlineCallbacks
+    def get_joined_groups(self, user_id):
+        group_ids = yield self.store.get_joined_groups(user_id)
+        defer.returnValue({"groups": group_ids})
+
+    @defer.inlineCallbacks
+    def get_publicised_groups_for_user(self, user_id):
+        if self.hs.is_mine_id(user_id):
+            result = yield self.store.get_publicised_groups_for_user(user_id)
+
+            # Check AS associated groups for this user - this depends on the
+            # RegExps in the AS registration file (under `users`)
+            for app_service in self.store.get_app_services():
+                result.extend(app_service.get_groups_for_user(user_id))
+
+            defer.returnValue({"groups": result})
+        else:
+            result = yield self.transport_client.get_publicised_groups_for_user(
+                get_domain_from_id(user_id), user_id
+            )
+            # TODO: Verify attestations
+            defer.returnValue(result)
+
+    @defer.inlineCallbacks
+    def bulk_get_publicised_groups(self, user_ids, proxy=True):
+        destinations = {}
+        local_users = set()
+
+        for user_id in user_ids:
+            if self.hs.is_mine_id(user_id):
+                local_users.add(user_id)
+            else:
+                destinations.setdefault(
+                    get_domain_from_id(user_id), set()
+                ).add(user_id)
+
+        if not proxy and destinations:
+            raise SynapseError(400, "Some user_ids are not local")
+
+        results = {}
+        failed_results = []
+        for destination, dest_user_ids in destinations.iteritems():
+            try:
+                r = yield self.transport_client.bulk_get_publicised_groups(
+                    destination, list(dest_user_ids),
+                )
+                results.update(r["users"])
+            except Exception:
+                failed_results.extend(dest_user_ids)
+
+        for uid in local_users:
+            results[uid] = yield self.store.get_publicised_groups_for_user(
+                uid
+            )
+
+            # Check AS associated groups for this user - this depends on the
+            # RegExps in the AS registration file (under `users`)
+            for app_service in self.store.get_app_services():
+                results[uid].extend(app_service.get_groups_for_user(uid))
+
+        defer.returnValue({"users": results})
diff --git a/synapse/handlers/initial_sync.py b/synapse/handlers/initial_sync.py
index 10f5f35a69..c5267b4b84 100644
--- a/synapse/handlers/initial_sync.py
+++ b/synapse/handlers/initial_sync.py
@@ -27,7 +27,7 @@ from synapse.types import (
 from synapse.util import unwrapFirstError
 from synapse.util.async import concurrently_execute
 from synapse.util.caches.snapshot_cache import SnapshotCache
-from synapse.util.logcontext import preserve_fn, preserve_context_over_deferred
+from synapse.util.logcontext import make_deferred_yieldable, preserve_fn
 from synapse.visibility import filter_events_for_client
 
 from ._base import BaseHandler
@@ -163,7 +163,7 @@ class InitialSyncHandler(BaseHandler):
                         lambda states: states[event.event_id]
                     )
 
-                (messages, token), current_state = yield preserve_context_over_deferred(
+                (messages, token), current_state = yield make_deferred_yieldable(
                     defer.gatherResults(
                         [
                             preserve_fn(self.store.get_recent_events_for_room)(
@@ -214,7 +214,7 @@ class InitialSyncHandler(BaseHandler):
                     })
 
                 d["account_data"] = account_data_events
-            except:
+            except Exception:
                 logger.exception("Failed to get snapshot")
 
         yield concurrently_execute(handle_room, room_list, 10)
diff --git a/synapse/handlers/message.py b/synapse/handlers/message.py
index f6740544c1..21f1717dd2 100644
--- a/synapse/handlers/message.py
+++ b/synapse/handlers/message.py
@@ -1,5 +1,6 @@
 # -*- coding: utf-8 -*-
 # Copyright 2014 - 2016 OpenMarket Ltd
+# Copyright 2017 New Vector Ltd
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -25,6 +26,7 @@ from synapse.types import (
 from synapse.util.async import run_on_reactor, ReadWriteLock, Limiter
 from synapse.util.logcontext import preserve_fn
 from synapse.util.metrics import measure_func
+from synapse.util.frozenutils import unfreeze
 from synapse.visibility import filter_events_for_client
 
 from ._base import BaseHandler
@@ -46,6 +48,7 @@ class MessageHandler(BaseHandler):
         self.state = hs.get_state_handler()
         self.clock = hs.get_clock()
         self.validator = EventValidator()
+        self.profile_handler = hs.get_profile_handler()
 
         self.pagination_lock = ReadWriteLock()
 
@@ -211,7 +214,7 @@ class MessageHandler(BaseHandler):
 
                 if membership in {Membership.JOIN, Membership.INVITE}:
                     # If event doesn't include a display name, add one.
-                    profile = self.hs.get_handlers().profile_handler
+                    profile = self.profile_handler
                     content = builder.content
 
                     try:
@@ -323,9 +326,12 @@ class MessageHandler(BaseHandler):
             txn_id=txn_id
         )
 
-        if self.spam_checker.check_event_for_spam(event):
+        spam_error = self.spam_checker.check_event_for_spam(event)
+        if spam_error:
+            if not isinstance(spam_error, basestring):
+                spam_error = "Spam is not permitted here"
             raise SynapseError(
-                403, "Spam is not permitted here", Codes.FORBIDDEN
+                403, spam_error, Codes.FORBIDDEN
             )
 
         yield self.send_nonmember_event(
@@ -420,27 +426,41 @@ class MessageHandler(BaseHandler):
         )
 
     @defer.inlineCallbacks
-    def get_joined_members(self, user_id, room_id):
+    def get_joined_members(self, requester, room_id):
         """Get all the joined members in the room and their profile information.
 
         If the user has left the room return the state events from when they left.
 
         Args:
-            user_id(str): The user requesting state events.
+            requester(Requester): The user requesting state events.
             room_id(str): The room ID to get all state events from.
         Returns:
             A dict of user_id to profile info
         """
-        membership, membership_event_id = yield self._check_in_room_or_world_readable(
-            room_id, user_id
-        )
-
-        if membership == Membership.JOIN:
-            users_with_profile = yield self.state.get_current_user_in_room(room_id)
-        else:
-            raise NotImplementedError(
-                "Getting joined members after leaving is not implemented"
+        user_id = requester.user.to_string()
+        if not requester.app_service:
+            # We check AS auth after fetching the room membership, as it
+            # requires us to pull out all joined members anyway.
+            membership, _ = yield self._check_in_room_or_world_readable(
+                room_id, user_id
             )
+            if membership != Membership.JOIN:
+                raise NotImplementedError(
+                    "Getting joined members after leaving is not implemented"
+                )
+
+        users_with_profile = yield self.state.get_current_user_in_room(room_id)
+
+        # If this is an AS, double check that they are allowed to see the members.
+        # This can either be because the AS user is in the room or becuase there
+        # is a user in the room that the AS is "interested in"
+        if requester.app_service and user_id not in users_with_profile:
+            for uid in users_with_profile:
+                if requester.app_service.is_interested_in_user(uid):
+                    break
+            else:
+                # Loop fell through, AS has no interested users in room
+                raise AuthError(403, "Appservice not in room")
 
         defer.returnValue({
             user_id: {
@@ -541,9 +561,9 @@ class MessageHandler(BaseHandler):
 
         # Ensure that we can round trip before trying to persist in db
         try:
-            dump = ujson.dumps(event.content)
+            dump = ujson.dumps(unfreeze(event.content))
             ujson.loads(dump)
-        except:
+        except Exception:
             logger.exception("Failed to encode content: %r", event.content)
             raise
 
diff --git a/synapse/handlers/presence.py b/synapse/handlers/presence.py
index c7c0b0a1e2..cb158ba962 100644
--- a/synapse/handlers/presence.py
+++ b/synapse/handlers/presence.py
@@ -364,7 +364,7 @@ class PresenceHandler(object):
                 )
 
             preserve_fn(self._update_states)(changes)
-        except:
+        except Exception:
             logger.exception("Exception in _handle_timeouts loop")
 
     @defer.inlineCallbacks
@@ -1199,7 +1199,7 @@ def handle_timeout(state, is_mine, syncing_user_ids, now):
                 )
                 changed = True
     else:
-        # We expect to be poked occaisonally by the other side.
+        # We expect to be poked occasionally by the other side.
         # This is to protect against forgetful/buggy servers, so that
         # no one gets stuck online forever.
         if now - state.last_federation_update_ts > FEDERATION_TIMEOUT:
diff --git a/synapse/handlers/profile.py b/synapse/handlers/profile.py
index 7abee98dea..9800e24453 100644
--- a/synapse/handlers/profile.py
+++ b/synapse/handlers/profile.py
@@ -17,16 +17,16 @@ import logging
 
 from twisted.internet import defer
 
-import synapse.types
 from synapse.api.errors import SynapseError, AuthError, CodeMessageException
-from synapse.types import UserID
+from synapse.types import UserID, get_domain_from_id
 from ._base import BaseHandler
 
-
 logger = logging.getLogger(__name__)
 
 
 class ProfileHandler(BaseHandler):
+    PROFILE_UPDATE_MS = 60 * 1000
+    PROFILE_UPDATE_EVERY_MS = 24 * 60 * 60 * 1000
 
     def __init__(self, hs):
         super(ProfileHandler, self).__init__(hs)
@@ -36,6 +36,65 @@ class ProfileHandler(BaseHandler):
             "profile", self.on_profile_query
         )
 
+        self.user_directory_handler = hs.get_user_directory_handler()
+
+        self.clock.looping_call(self._update_remote_profile_cache, self.PROFILE_UPDATE_MS)
+
+    @defer.inlineCallbacks
+    def get_profile(self, user_id):
+        target_user = UserID.from_string(user_id)
+        if self.hs.is_mine(target_user):
+            displayname = yield self.store.get_profile_displayname(
+                target_user.localpart
+            )
+            avatar_url = yield self.store.get_profile_avatar_url(
+                target_user.localpart
+            )
+
+            defer.returnValue({
+                "displayname": displayname,
+                "avatar_url": avatar_url,
+            })
+        else:
+            try:
+                result = yield self.federation.make_query(
+                    destination=target_user.domain,
+                    query_type="profile",
+                    args={
+                        "user_id": user_id,
+                    },
+                    ignore_backoff=True,
+                )
+                defer.returnValue(result)
+            except CodeMessageException as e:
+                if e.code != 404:
+                    logger.exception("Failed to get displayname")
+
+                raise
+
+    @defer.inlineCallbacks
+    def get_profile_from_cache(self, user_id):
+        """Get the profile information from our local cache. If the user is
+        ours then the profile information will always be corect. Otherwise,
+        it may be out of date/missing.
+        """
+        target_user = UserID.from_string(user_id)
+        if self.hs.is_mine(target_user):
+            displayname = yield self.store.get_profile_displayname(
+                target_user.localpart
+            )
+            avatar_url = yield self.store.get_profile_avatar_url(
+                target_user.localpart
+            )
+
+            defer.returnValue({
+                "displayname": displayname,
+                "avatar_url": avatar_url,
+            })
+        else:
+            profile = yield self.store.get_from_remote_profile_cache(user_id)
+            defer.returnValue(profile or {})
+
     @defer.inlineCallbacks
     def get_displayname(self, target_user):
         if self.hs.is_mine(target_user):
@@ -60,7 +119,7 @@ class ProfileHandler(BaseHandler):
                     logger.exception("Failed to get displayname")
 
                 raise
-            except:
+            except Exception:
                 logger.exception("Failed to get displayname")
             else:
                 defer.returnValue(result["displayname"])
@@ -82,7 +141,13 @@ class ProfileHandler(BaseHandler):
             target_user.localpart, new_displayname
         )
 
-        yield self._update_join_states(requester)
+        if self.hs.config.user_directory_search_all_users:
+            profile = yield self.store.get_profileinfo(target_user.localpart)
+            yield self.user_directory_handler.handle_local_profile_change(
+                target_user.to_string(), profile
+            )
+
+        yield self._update_join_states(requester, target_user)
 
     @defer.inlineCallbacks
     def get_avatar_url(self, target_user):
@@ -107,7 +172,7 @@ class ProfileHandler(BaseHandler):
                 if e.code != 404:
                     logger.exception("Failed to get avatar_url")
                 raise
-            except:
+            except Exception:
                 logger.exception("Failed to get avatar_url")
 
             defer.returnValue(result["avatar_url"])
@@ -126,7 +191,13 @@ class ProfileHandler(BaseHandler):
             target_user.localpart, new_avatar_url
         )
 
-        yield self._update_join_states(requester)
+        if self.hs.config.user_directory_search_all_users:
+            profile = yield self.store.get_profileinfo(target_user.localpart)
+            yield self.user_directory_handler.handle_local_profile_change(
+                target_user.to_string(), profile
+            )
+
+        yield self._update_join_states(requester, target_user)
 
     @defer.inlineCallbacks
     def on_profile_query(self, args):
@@ -151,28 +222,24 @@ class ProfileHandler(BaseHandler):
         defer.returnValue(response)
 
     @defer.inlineCallbacks
-    def _update_join_states(self, requester):
-        user = requester.user
-        if not self.hs.is_mine(user):
+    def _update_join_states(self, requester, target_user):
+        if not self.hs.is_mine(target_user):
             return
 
         yield self.ratelimit(requester)
 
         room_ids = yield self.store.get_rooms_for_user(
-            user.to_string(),
+            target_user.to_string(),
         )
 
         for room_id in room_ids:
             handler = self.hs.get_handlers().room_member_handler
             try:
-                # Assume the user isn't a guest because we don't let guests set
-                # profile or avatar data.
-                # XXX why are we recreating `requester` here for each room?
-                # what was wrong with the `requester` we were passed?
-                requester = synapse.types.create_requester(user)
+                # Assume the target_user isn't a guest,
+                # because we don't let guests set profile or avatar data.
                 yield handler.update_membership(
                     requester,
-                    user,
+                    target_user,
                     room_id,
                     "join",  # We treat a profile update like a join.
                     ratelimit=False,  # Try to hide that these events aren't atomic.
@@ -182,3 +249,44 @@ class ProfileHandler(BaseHandler):
                     "Failed to update join event for room %s - %s",
                     room_id, str(e.message)
                 )
+
+    def _update_remote_profile_cache(self):
+        """Called periodically to check profiles of remote users we haven't
+        checked in a while.
+        """
+        entries = yield self.store.get_remote_profile_cache_entries_that_expire(
+            last_checked=self.clock.time_msec() - self.PROFILE_UPDATE_EVERY_MS
+        )
+
+        for user_id, displayname, avatar_url in entries:
+            is_subscribed = yield self.store.is_subscribed_remote_profile_for_user(
+                user_id,
+            )
+            if not is_subscribed:
+                yield self.store.maybe_delete_remote_profile_cache(user_id)
+                continue
+
+            try:
+                profile = yield self.federation.make_query(
+                    destination=get_domain_from_id(user_id),
+                    query_type="profile",
+                    args={
+                        "user_id": user_id,
+                    },
+                    ignore_backoff=True,
+                )
+            except Exception:
+                logger.exception("Failed to get avatar_url")
+
+                yield self.store.update_remote_profile_cache(
+                    user_id, displayname, avatar_url
+                )
+                continue
+
+            new_name = profile.get("displayname")
+            new_avatar = profile.get("avatar_url")
+
+            # We always hit update to update the last_check timestamp
+            yield self.store.update_remote_profile_cache(
+                user_id, new_name, new_avatar
+            )
diff --git a/synapse/handlers/receipts.py b/synapse/handlers/receipts.py
index e1cd3a48e9..0525765272 100644
--- a/synapse/handlers/receipts.py
+++ b/synapse/handlers/receipts.py
@@ -12,6 +12,7 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
+from synapse.util import logcontext
 
 from ._base import BaseHandler
 
@@ -59,6 +60,8 @@ class ReceiptsHandler(BaseHandler):
         is_new = yield self._handle_new_receipts([receipt])
 
         if is_new:
+            # fire off a process in the background to send the receipt to
+            # remote servers
             self._push_remotes([receipt])
 
     @defer.inlineCallbacks
@@ -126,6 +129,7 @@ class ReceiptsHandler(BaseHandler):
 
             defer.returnValue(True)
 
+    @logcontext.preserve_fn   # caller should not yield on this
     @defer.inlineCallbacks
     def _push_remotes(self, receipts):
         """Given a list of receipts, works out which remote servers should be
diff --git a/synapse/handlers/register.py b/synapse/handlers/register.py
index ee3a2269a8..4bc6ef51fe 100644
--- a/synapse/handlers/register.py
+++ b/synapse/handlers/register.py
@@ -15,7 +15,6 @@
 
 """Contains functions for registering clients."""
 import logging
-import urllib
 
 from twisted.internet import defer
 
@@ -23,6 +22,7 @@ from synapse.api.errors import (
     AuthError, Codes, SynapseError, RegistrationError, InvalidCaptchaError
 )
 from synapse.http.client import CaptchaServerHttpClient
+from synapse import types
 from synapse.types import UserID
 from synapse.util.async import run_on_reactor
 from ._base import BaseHandler
@@ -36,6 +36,9 @@ class RegistrationHandler(BaseHandler):
         super(RegistrationHandler, self).__init__(hs)
 
         self.auth = hs.get_auth()
+        self._auth_handler = hs.get_auth_handler()
+        self.profile_handler = hs.get_profile_handler()
+        self.user_directory_handler = hs.get_user_directory_handler()
         self.captcha_client = CaptchaServerHttpClient(hs)
 
         self._next_generated_user_id = None
@@ -45,12 +48,10 @@ class RegistrationHandler(BaseHandler):
     @defer.inlineCallbacks
     def check_username(self, localpart, guest_access_token=None,
                        assigned_user_id=None):
-        yield run_on_reactor()
-
-        if urllib.quote(localpart.encode('utf-8')) != localpart:
+        if types.contains_invalid_mxid_characters(localpart):
             raise SynapseError(
                 400,
-                "User ID can only contain characters a-z, 0-9, or '_-./'",
+                "User ID can only contain characters a-z, 0-9, or '=_-./'",
                 Codes.INVALID_USERNAME
             )
 
@@ -80,7 +81,7 @@ class RegistrationHandler(BaseHandler):
                     "A different user ID has already been registered for this session",
                 )
 
-        yield self.check_user_id_not_appservice_exclusive(user_id)
+        self.check_user_id_not_appservice_exclusive(user_id)
 
         users = yield self.store.get_users_by_id_case_insensitive(user_id)
         if users:
@@ -165,6 +166,13 @@ class RegistrationHandler(BaseHandler):
                 ),
                 admin=admin,
             )
+
+            if self.hs.config.user_directory_search_all_users:
+                profile = yield self.store.get_profileinfo(localpart)
+                yield self.user_directory_handler.handle_local_profile_change(
+                    user_id, profile
+                )
+
         else:
             # autogen a sequential user ID
             attempts = 0
@@ -253,11 +261,10 @@ class RegistrationHandler(BaseHandler):
         """
         Registers email_id as SAML2 Based Auth.
         """
-        if urllib.quote(localpart) != localpart:
+        if types.contains_invalid_mxid_characters(localpart):
             raise SynapseError(
                 400,
-                "User ID must only contain characters which do not"
-                " require URL encoding."
+                "User ID can only contain characters a-z, 0-9, or '=_-./'",
             )
         user = UserID(localpart, self.hs.hostname)
         user_id = user.to_string()
@@ -291,7 +298,7 @@ class RegistrationHandler(BaseHandler):
             try:
                 identity_handler = self.hs.get_handlers().identity_handler
                 threepid = yield identity_handler.threepid_from_creds(c)
-            except:
+            except Exception:
                 logger.exception("Couldn't validate 3pid")
                 raise RegistrationError(400, "Couldn't validate 3pid")
 
@@ -418,13 +425,12 @@ class RegistrationHandler(BaseHandler):
                 create_profile_with_localpart=user.localpart,
             )
         else:
-            yield self.store.user_delete_access_tokens(user_id=user_id)
+            yield self._auth_handler.delete_access_tokens_for_user(user_id)
             yield self.store.add_access_token_to_user(user_id=user_id, token=token)
 
         if displayname is not None:
             logger.info("setting user display name: %s -> %s", user_id, displayname)
-            profile_handler = self.hs.get_handlers().profile_handler
-            yield profile_handler.set_displayname(
+            yield self.profile_handler.set_displayname(
                 user, requester, displayname, by_admin=True,
             )
 
diff --git a/synapse/handlers/room.py b/synapse/handlers/room.py
index 5698d28088..d1cc87a016 100644
--- a/synapse/handlers/room.py
+++ b/synapse/handlers/room.py
@@ -60,6 +60,11 @@ class RoomCreationHandler(BaseHandler):
         },
     }
 
+    def __init__(self, hs):
+        super(RoomCreationHandler, self).__init__(hs)
+
+        self.spam_checker = hs.get_spam_checker()
+
     @defer.inlineCallbacks
     def create_room(self, requester, config, ratelimit=True):
         """ Creates a new room.
@@ -75,6 +80,9 @@ class RoomCreationHandler(BaseHandler):
         """
         user_id = requester.user.to_string()
 
+        if not self.spam_checker.user_may_create_room(user_id):
+            raise SynapseError(403, "You are not permitted to create rooms")
+
         if ratelimit:
             yield self.ratelimit(requester)
 
@@ -83,7 +91,7 @@ class RoomCreationHandler(BaseHandler):
                 if wchar in config["room_alias_name"]:
                     raise SynapseError(400, "Invalid characters in room alias")
 
-            room_alias = RoomAlias.create(
+            room_alias = RoomAlias(
                 config["room_alias_name"],
                 self.hs.hostname,
             )
@@ -100,7 +108,7 @@ class RoomCreationHandler(BaseHandler):
         for i in invite_list:
             try:
                 UserID.from_string(i)
-            except:
+            except Exception:
                 raise SynapseError(400, "Invalid user_id: %s" % (i,))
 
         invite_3pid_list = config.get("invite_3pid", [])
@@ -115,7 +123,7 @@ class RoomCreationHandler(BaseHandler):
         while attempts < 5:
             try:
                 random_string = stringutils.random_string(18)
-                gen_room_id = RoomID.create(
+                gen_room_id = RoomID(
                     random_string,
                     self.hs.hostname,
                 )
@@ -197,12 +205,12 @@ class RoomCreationHandler(BaseHandler):
                 },
                 ratelimit=False)
 
-        content = {}
-        is_direct = config.get("is_direct", None)
-        if is_direct:
-            content["is_direct"] = is_direct
-
         for invitee in invite_list:
+            content = {}
+            is_direct = config.get("is_direct", None)
+            if is_direct:
+                content["is_direct"] = is_direct
+
             yield room_member_handler.update_membership(
                 requester,
                 UserID.from_string(invitee),
diff --git a/synapse/handlers/room_list.py b/synapse/handlers/room_list.py
index 516cd9a6ac..bb40075387 100644
--- a/synapse/handlers/room_list.py
+++ b/synapse/handlers/room_list.py
@@ -20,6 +20,7 @@ from ._base import BaseHandler
 from synapse.api.constants import (
     EventTypes, JoinRules,
 )
+from synapse.util.logcontext import make_deferred_yieldable, preserve_fn
 from synapse.util.async import concurrently_execute
 from synapse.util.caches.descriptors import cachedInlineCallbacks
 from synapse.util.caches.response_cache import ResponseCache
@@ -70,6 +71,7 @@ class RoomListHandler(BaseHandler):
         if search_filter:
             # We explicitly don't bother caching searches or requests for
             # appservice specific lists.
+            logger.info("Bypassing cache as search request.")
             return self._get_public_room_list(
                 limit, since_token, search_filter, network_tuple=network_tuple,
             )
@@ -77,13 +79,16 @@ class RoomListHandler(BaseHandler):
         key = (limit, since_token, network_tuple)
         result = self.response_cache.get(key)
         if not result:
+            logger.info("No cached result, calculating one.")
             result = self.response_cache.set(
                 key,
-                self._get_public_room_list(
+                preserve_fn(self._get_public_room_list)(
                     limit, since_token, network_tuple=network_tuple
                 )
             )
-        return result
+        else:
+            logger.info("Using cached deferred result.")
+        return make_deferred_yieldable(result)
 
     @defer.inlineCallbacks
     def _get_public_room_list(self, limit=None, since_token=None,
@@ -149,6 +154,8 @@ class RoomListHandler(BaseHandler):
             # We want larger rooms to be first, hence negating num_joined_users
             rooms_to_order_value[room_id] = (-num_joined_users, room_id)
 
+        logger.info("Getting ordering for %i rooms since %s",
+                    len(room_ids), stream_token)
         yield concurrently_execute(get_order_for_room, room_ids, 10)
 
         sorted_entries = sorted(rooms_to_order_value.items(), key=lambda e: e[1])
@@ -176,34 +183,42 @@ class RoomListHandler(BaseHandler):
                 rooms_to_scan = rooms_to_scan[:since_token.current_limit]
                 rooms_to_scan.reverse()
 
-        # Actually generate the entries. _append_room_entry_to_chunk will append to
-        # chunk but will stop if len(chunk) > limit
-        chunk = []
-        if limit and not search_filter:
+        logger.info("After sorting and filtering, %i rooms remain",
+                    len(rooms_to_scan))
+
+        # _append_room_entry_to_chunk will append to chunk but will stop if
+        # len(chunk) > limit
+        #
+        # Normally we will generate enough results on the first iteration here,
+        #  but if there is a search filter, _append_room_entry_to_chunk may
+        # filter some results out, in which case we loop again.
+        #
+        # We don't want to scan over the entire range either as that
+        # would potentially waste a lot of work.
+        #
+        # XXX if there is no limit, we may end up DoSing the server with
+        # calls to get_current_state_ids for every single room on the
+        # server. Surely we should cap this somehow?
+        #
+        if limit:
             step = limit + 1
-            for i in xrange(0, len(rooms_to_scan), step):
-                # We iterate here because the vast majority of cases we'll stop
-                # at first iteration, but occaisonally _append_room_entry_to_chunk
-                # won't append to the chunk and so we need to loop again.
-                # We don't want to scan over the entire range either as that
-                # would potentially waste a lot of work.
-                yield concurrently_execute(
-                    lambda r: self._append_room_entry_to_chunk(
-                        r, rooms_to_num_joined[r],
-                        chunk, limit, search_filter
-                    ),
-                    rooms_to_scan[i:i + step], 10
-                )
-                if len(chunk) >= limit + 1:
-                    break
         else:
+            step = len(rooms_to_scan)
+
+        chunk = []
+        for i in xrange(0, len(rooms_to_scan), step):
+            batch = rooms_to_scan[i:i + step]
+            logger.info("Processing %i rooms for result", len(batch))
             yield concurrently_execute(
                 lambda r: self._append_room_entry_to_chunk(
                     r, rooms_to_num_joined[r],
                     chunk, limit, search_filter
                 ),
-                rooms_to_scan, 5
+                batch, 5,
             )
+            logger.info("Now %i rooms in result", len(chunk))
+            if len(chunk) >= limit + 1:
+                break
 
         chunk.sort(key=lambda e: (-e["num_joined_members"], e["room_id"]))
 
@@ -276,13 +291,14 @@ class RoomListHandler(BaseHandler):
             # We've already got enough, so lets just drop it.
             return
 
-        result = yield self._generate_room_entry(room_id, num_joined_users)
+        result = yield self.generate_room_entry(room_id, num_joined_users)
 
         if result and _matches_room_entry(result, search_filter):
             chunk.append(result)
 
     @cachedInlineCallbacks(num_args=1, cache_context=True)
-    def _generate_room_entry(self, room_id, num_joined_users, cache_context):
+    def generate_room_entry(self, room_id, num_joined_users, cache_context,
+                            with_alias=True, allow_private=False):
         """Returns the entry for a room
         """
         result = {
@@ -316,14 +332,15 @@ class RoomListHandler(BaseHandler):
         join_rules_event = current_state.get((EventTypes.JoinRules, ""))
         if join_rules_event:
             join_rule = join_rules_event.content.get("join_rule", None)
-            if join_rule and join_rule != JoinRules.PUBLIC:
+            if not allow_private and join_rule and join_rule != JoinRules.PUBLIC:
                 defer.returnValue(None)
 
-        aliases = yield self.store.get_aliases_for_room(
-            room_id, on_invalidate=cache_context.invalidate
-        )
-        if aliases:
-            result["aliases"] = aliases
+        if with_alias:
+            aliases = yield self.store.get_aliases_for_room(
+                room_id, on_invalidate=cache_context.invalidate
+            )
+            if aliases:
+                result["aliases"] = aliases
 
         name_event = yield current_state.get((EventTypes.Name, ""))
         if name_event:
diff --git a/synapse/handlers/room_member.py b/synapse/handlers/room_member.py
index 9a498c2d3e..7e6467cd1d 100644
--- a/synapse/handlers/room_member.py
+++ b/synapse/handlers/room_member.py
@@ -45,9 +45,12 @@ class RoomMemberHandler(BaseHandler):
     def __init__(self, hs):
         super(RoomMemberHandler, self).__init__(hs)
 
+        self.profile_handler = hs.get_profile_handler()
+
         self.member_linearizer = Linearizer(name="member")
 
         self.clock = hs.get_clock()
+        self.spam_checker = hs.get_spam_checker()
 
         self.distributor = hs.get_distributor()
         self.distributor.declare("user_joined_room")
@@ -186,6 +189,10 @@ class RoomMemberHandler(BaseHandler):
         content_specified = bool(content)
         if content is None:
             content = {}
+        else:
+            # We do a copy here as we potentially change some keys
+            # later on.
+            content = dict(content)
 
         effective_membership_state = action
         if action in ["kick", "unban"]:
@@ -210,12 +217,26 @@ class RoomMemberHandler(BaseHandler):
             if is_blocked:
                 raise SynapseError(403, "This room has been blocked on this server")
 
-        if (effective_membership_state == "invite" and
-                self.hs.config.block_non_admin_invites):
+        if effective_membership_state == "invite":
+            block_invite = False
             is_requester_admin = yield self.auth.is_server_admin(
                 requester.user,
             )
             if not is_requester_admin:
+                if self.hs.config.block_non_admin_invites:
+                    logger.info(
+                        "Blocking invite: user is not admin and non-admin "
+                        "invites disabled"
+                    )
+                    block_invite = True
+
+                if not self.spam_checker.user_may_invite(
+                    requester.user.to_string(), target.to_string(), room_id,
+                ):
+                    logger.info("Blocking invite due to spam checker")
+                    block_invite = True
+
+            if block_invite:
                 raise SynapseError(
                     403, "Invites have been disabled on this server",
                 )
@@ -267,7 +288,7 @@ class RoomMemberHandler(BaseHandler):
 
                 content["membership"] = Membership.JOIN
 
-                profile = self.hs.get_handlers().profile_handler
+                profile = self.profile_handler
                 if not content_specified:
                     content["displayname"] = yield profile.get_displayname(target)
                     content["avatar_url"] = yield profile.get_avatar_url(target)
diff --git a/synapse/handlers/search.py b/synapse/handlers/search.py
index df75d70fac..9772ed1a0e 100644
--- a/synapse/handlers/search.py
+++ b/synapse/handlers/search.py
@@ -61,7 +61,7 @@ class SearchHandler(BaseHandler):
                 assert batch_group is not None
                 assert batch_group_key is not None
                 assert batch_token is not None
-            except:
+            except Exception:
                 raise SynapseError(400, "Invalid batch")
 
         try:
diff --git a/synapse/handlers/set_password.py b/synapse/handlers/set_password.py
new file mode 100644
index 0000000000..44414e1dc1
--- /dev/null
+++ b/synapse/handlers/set_password.py
@@ -0,0 +1,56 @@
+# -*- coding: utf-8 -*-
+# Copyright 2017 New Vector Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+import logging
+
+from twisted.internet import defer
+
+from synapse.api.errors import Codes, StoreError, SynapseError
+from ._base import BaseHandler
+
+logger = logging.getLogger(__name__)
+
+
+class SetPasswordHandler(BaseHandler):
+    """Handler which deals with changing user account passwords"""
+    def __init__(self, hs):
+        super(SetPasswordHandler, self).__init__(hs)
+        self._auth_handler = hs.get_auth_handler()
+        self._device_handler = hs.get_device_handler()
+
+    @defer.inlineCallbacks
+    def set_password(self, user_id, newpassword, requester=None):
+        password_hash = self._auth_handler.hash(newpassword)
+
+        except_device_id = requester.device_id if requester else None
+        except_access_token_id = requester.access_token_id if requester else None
+
+        try:
+            yield self.store.user_set_password_hash(user_id, password_hash)
+        except StoreError as e:
+            if e.code == 404:
+                raise SynapseError(404, "Unknown user", Codes.NOT_FOUND)
+            raise e
+
+        # we want to log out all of the user's other sessions. First delete
+        # all his other devices.
+        yield self._device_handler.delete_all_devices_for_user(
+            user_id, except_device_id=except_device_id,
+        )
+
+        # and now delete any access tokens which weren't associated with
+        # devices (or were associated with this device).
+        yield self._auth_handler.delete_access_tokens_for_user(
+            user_id, except_token_id=except_access_token_id,
+        )
diff --git a/synapse/handlers/sync.py b/synapse/handlers/sync.py
index dd0ec00ae6..b12988f3c9 100644
--- a/synapse/handlers/sync.py
+++ b/synapse/handlers/sync.py
@@ -15,7 +15,7 @@
 
 from synapse.api.constants import Membership, EventTypes
 from synapse.util.async import concurrently_execute
-from synapse.util.logcontext import LoggingContext
+from synapse.util.logcontext import LoggingContext, make_deferred_yieldable, preserve_fn
 from synapse.util.metrics import Measure, measure_func
 from synapse.util.caches.response_cache import ResponseCache
 from synapse.push.clientformat import format_push_rules_for_user
@@ -108,6 +108,17 @@ class InvitedSyncResult(collections.namedtuple("InvitedSyncResult", [
         return True
 
 
+class GroupsSyncResult(collections.namedtuple("GroupsSyncResult", [
+    "join",
+    "invite",
+    "leave",
+])):
+    __slots__ = []
+
+    def __nonzero__(self):
+        return bool(self.join or self.invite or self.leave)
+
+
 class DeviceLists(collections.namedtuple("DeviceLists", [
     "changed",   # list of user_ids whose devices may have changed
     "left",      # list of user_ids whose devices we no longer track
@@ -129,6 +140,7 @@ class SyncResult(collections.namedtuple("SyncResult", [
     "device_lists",  # List of user_ids whose devices have chanegd
     "device_one_time_keys_count",  # Dict of algorithm to count for one time keys
                                    # for this device
+    "groups",
 ])):
     __slots__ = []
 
@@ -144,7 +156,8 @@ class SyncResult(collections.namedtuple("SyncResult", [
             self.archived or
             self.account_data or
             self.to_device or
-            self.device_lists
+            self.device_lists or
+            self.groups
         )
 
 
@@ -171,11 +184,11 @@ class SyncHandler(object):
         if not result:
             result = self.response_cache.set(
                 sync_config.request_key,
-                self._wait_for_sync_for_user(
+                preserve_fn(self._wait_for_sync_for_user)(
                     sync_config, since_token, timeout, full_state
                 )
             )
-        return result
+        return make_deferred_yieldable(result)
 
     @defer.inlineCallbacks
     def _wait_for_sync_for_user(self, sync_config, since_token, timeout,
@@ -595,6 +608,8 @@ class SyncHandler(object):
                 user_id, device_id
             )
 
+        yield self._generate_sync_entry_for_groups(sync_result_builder)
+
         defer.returnValue(SyncResult(
             presence=sync_result_builder.presence,
             account_data=sync_result_builder.account_data,
@@ -603,10 +618,57 @@ class SyncHandler(object):
             archived=sync_result_builder.archived,
             to_device=sync_result_builder.to_device,
             device_lists=device_lists,
+            groups=sync_result_builder.groups,
             device_one_time_keys_count=one_time_key_counts,
             next_batch=sync_result_builder.now_token,
         ))
 
+    @measure_func("_generate_sync_entry_for_groups")
+    @defer.inlineCallbacks
+    def _generate_sync_entry_for_groups(self, sync_result_builder):
+        user_id = sync_result_builder.sync_config.user.to_string()
+        since_token = sync_result_builder.since_token
+        now_token = sync_result_builder.now_token
+
+        if since_token and since_token.groups_key:
+            results = yield self.store.get_groups_changes_for_user(
+                user_id, since_token.groups_key, now_token.groups_key,
+            )
+        else:
+            results = yield self.store.get_all_groups_for_user(
+                user_id, now_token.groups_key,
+            )
+
+        invited = {}
+        joined = {}
+        left = {}
+        for result in results:
+            membership = result["membership"]
+            group_id = result["group_id"]
+            gtype = result["type"]
+            content = result["content"]
+
+            if membership == "join":
+                if gtype == "membership":
+                    # TODO: Add profile
+                    content.pop("membership", None)
+                    joined[group_id] = content["content"]
+                else:
+                    joined.setdefault(group_id, {})[gtype] = content
+            elif membership == "invite":
+                if gtype == "membership":
+                    content.pop("membership", None)
+                    invited[group_id] = content["content"]
+            else:
+                if gtype == "membership":
+                    left[group_id] = content["content"]
+
+        sync_result_builder.groups = GroupsSyncResult(
+            join=joined,
+            invite=invited,
+            leave=left,
+        )
+
     @measure_func("_generate_sync_entry_for_device_list")
     @defer.inlineCallbacks
     def _generate_sync_entry_for_device_list(self, sync_result_builder,
@@ -1368,6 +1430,7 @@ class SyncResultBuilder(object):
         self.invited = []
         self.archived = []
         self.device = []
+        self.groups = None
         self.to_device = []
 
 
diff --git a/synapse/handlers/user_directory.py b/synapse/handlers/user_directory.py
index 2a49456bfc..714f0195c8 100644
--- a/synapse/handlers/user_directory.py
+++ b/synapse/handlers/user_directory.py
@@ -20,12 +20,13 @@ from synapse.api.constants import EventTypes, JoinRules, Membership
 from synapse.storage.roommember import ProfileInfo
 from synapse.util.metrics import Measure
 from synapse.util.async import sleep
+from synapse.types import get_localpart_from_id
 
 
 logger = logging.getLogger(__name__)
 
 
-class UserDirectoyHandler(object):
+class UserDirectoryHandler(object):
     """Handles querying of and keeping updated the user_directory.
 
     N.B.: ASSUMES IT IS THE ONLY THING THAT MODIFIES THE USER DIRECTORY
@@ -41,9 +42,10 @@ class UserDirectoyHandler(object):
     one public room.
     """
 
-    INITIAL_SLEEP_MS = 50
-    INITIAL_SLEEP_COUNT = 100
-    INITIAL_BATCH_SIZE = 100
+    INITIAL_ROOM_SLEEP_MS = 50
+    INITIAL_ROOM_SLEEP_COUNT = 100
+    INITIAL_ROOM_BATCH_SIZE = 100
+    INITIAL_USER_SLEEP_MS = 10
 
     def __init__(self, hs):
         self.store = hs.get_datastore()
@@ -53,6 +55,7 @@ class UserDirectoyHandler(object):
         self.notifier = hs.get_notifier()
         self.is_mine_id = hs.is_mine_id
         self.update_user_directory = hs.config.update_user_directory
+        self.search_all_users = hs.config.user_directory_search_all_users
 
         # When start up for the first time we need to populate the user_directory.
         # This is a set of user_id's we've inserted already
@@ -111,6 +114,15 @@ class UserDirectoyHandler(object):
             self._is_processing = False
 
     @defer.inlineCallbacks
+    def handle_local_profile_change(self, user_id, profile):
+        """Called to update index of our local user profiles when they change
+        irrespective of any rooms the user may be in.
+        """
+        yield self.store.update_profile_in_user_dir(
+            user_id, profile.display_name, profile.avatar_url, None,
+        )
+
+    @defer.inlineCallbacks
     def _unsafe_process(self):
         # If self.pos is None then means we haven't fetched it from DB
         if self.pos is None:
@@ -148,16 +160,30 @@ class UserDirectoyHandler(object):
         room_ids = yield self.store.get_all_rooms()
 
         logger.info("Doing initial update of user directory. %d rooms", len(room_ids))
-        num_processed_rooms = 1
+        num_processed_rooms = 0
 
         for room_id in room_ids:
-            logger.info("Handling room %d/%d", num_processed_rooms, len(room_ids))
-            yield self._handle_intial_room(room_id)
+            logger.info("Handling room %d/%d", num_processed_rooms + 1, len(room_ids))
+            yield self._handle_initial_room(room_id)
             num_processed_rooms += 1
-            yield sleep(self.INITIAL_SLEEP_MS / 1000.)
+            yield sleep(self.INITIAL_ROOM_SLEEP_MS / 1000.)
 
         logger.info("Processed all rooms.")
 
+        if self.search_all_users:
+            num_processed_users = 0
+            user_ids = yield self.store.get_all_local_users()
+            logger.info("Doing initial update of user directory. %d users", len(user_ids))
+            for user_id in user_ids:
+                # We add profiles for all users even if they don't match the
+                # include pattern, just in case we want to change it in future
+                logger.info("Handling user %d/%d", num_processed_users + 1, len(user_ids))
+                yield self._handle_local_user(user_id)
+                num_processed_users += 1
+                yield sleep(self.INITIAL_USER_SLEEP_MS / 1000.)
+
+            logger.info("Processed all users")
+
         self.initially_handled_users = None
         self.initially_handled_users_in_public = None
         self.initially_handled_users_share = None
@@ -166,7 +192,7 @@ class UserDirectoyHandler(object):
         yield self.store.update_user_directory_stream_pos(new_pos)
 
     @defer.inlineCallbacks
-    def _handle_intial_room(self, room_id):
+    def _handle_initial_room(self, room_id):
         """Called when we initially fill out user_directory one room at a time
         """
         is_in_room = yield self.store.is_host_joined(room_id, self.server_name)
@@ -201,8 +227,8 @@ class UserDirectoyHandler(object):
         to_update = set()
         count = 0
         for user_id in user_ids:
-            if count % self.INITIAL_SLEEP_COUNT == 0:
-                yield sleep(self.INITIAL_SLEEP_MS / 1000.)
+            if count % self.INITIAL_ROOM_SLEEP_COUNT == 0:
+                yield sleep(self.INITIAL_ROOM_SLEEP_MS / 1000.)
 
             if not self.is_mine_id(user_id):
                 count += 1
@@ -216,8 +242,8 @@ class UserDirectoyHandler(object):
                 if user_id == other_user_id:
                     continue
 
-                if count % self.INITIAL_SLEEP_COUNT == 0:
-                    yield sleep(self.INITIAL_SLEEP_MS / 1000.)
+                if count % self.INITIAL_ROOM_SLEEP_COUNT == 0:
+                    yield sleep(self.INITIAL_ROOM_SLEEP_MS / 1000.)
                 count += 1
 
                 user_set = (user_id, other_user_id)
@@ -237,13 +263,13 @@ class UserDirectoyHandler(object):
                 else:
                     self.initially_handled_users_share_private_room.add(user_set)
 
-                if len(to_insert) > self.INITIAL_BATCH_SIZE:
+                if len(to_insert) > self.INITIAL_ROOM_BATCH_SIZE:
                     yield self.store.add_users_who_share_room(
                         room_id, not is_public, to_insert,
                     )
                     to_insert.clear()
 
-                if len(to_update) > self.INITIAL_BATCH_SIZE:
+                if len(to_update) > self.INITIAL_ROOM_BATCH_SIZE:
                     yield self.store.update_users_who_share_room(
                         room_id, not is_public, to_update,
                     )
@@ -385,14 +411,28 @@ class UserDirectoyHandler(object):
                 yield self._handle_remove_user(room_id, user_id)
 
     @defer.inlineCallbacks
+    def _handle_local_user(self, user_id):
+        """Adds a new local roomless user into the user_directory_search table.
+        Used to populate up the user index when we have an
+        user_directory_search_all_users specified.
+        """
+        logger.debug("Adding new local user to dir, %r", user_id)
+
+        profile = yield self.store.get_profileinfo(get_localpart_from_id(user_id))
+
+        row = yield self.store.get_user_in_directory(user_id)
+        if not row:
+            yield self.store.add_profiles_to_user_dir(None, {user_id: profile})
+
+    @defer.inlineCallbacks
     def _handle_new_user(self, room_id, user_id, profile):
         """Called when we might need to add user to directory
 
         Args:
-            room_id (str): room_id that user joined or started being public that
+            room_id (str): room_id that user joined or started being public
             user_id (str)
         """
-        logger.debug("Adding user to dir, %r", user_id)
+        logger.debug("Adding new user to dir, %r", user_id)
 
         row = yield self.store.get_user_in_directory(user_id)
         if not row:
@@ -407,7 +447,7 @@ class UserDirectoyHandler(object):
             if not row:
                 yield self.store.add_users_to_public_room(room_id, [user_id])
         else:
-            logger.debug("Not adding user to public dir, %r", user_id)
+            logger.debug("Not adding new user to public dir, %r", user_id)
 
         # Now we update users who share rooms with users. We do this by getting
         # all the current users in the room and seeing which aren't already
diff --git a/synapse/http/additional_resource.py b/synapse/http/additional_resource.py
new file mode 100644
index 0000000000..343e932cb1
--- /dev/null
+++ b/synapse/http/additional_resource.py
@@ -0,0 +1,55 @@
+# -*- coding: utf-8 -*-
+# Copyright 2017 New Vector Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from synapse.http.server import wrap_request_handler
+from twisted.web.resource import Resource
+from twisted.web.server import NOT_DONE_YET
+
+
+class AdditionalResource(Resource):
+    """Resource wrapper for additional_resources
+
+    If the user has configured additional_resources, we need to wrap the
+    handler class with a Resource so that we can map it into the resource tree.
+
+    This class is also where we wrap the request handler with logging, metrics,
+    and exception handling.
+    """
+    def __init__(self, hs, handler):
+        """Initialise AdditionalResource
+
+        The ``handler`` should return a deferred which completes when it has
+        done handling the request. It should write a response with
+        ``request.write()``, and call ``request.finish()``.
+
+        Args:
+            hs (synapse.server.HomeServer): homeserver
+            handler ((twisted.web.server.Request) -> twisted.internet.defer.Deferred):
+                function to be called to handle the request.
+        """
+        Resource.__init__(self)
+        self._handler = handler
+
+        # these are required by the request_handler wrapper
+        self.version_string = hs.version_string
+        self.clock = hs.get_clock()
+
+    def render(self, request):
+        self._async_render(request)
+        return NOT_DONE_YET
+
+    @wrap_request_handler
+    def _async_render(self, request):
+        return self._handler(request)
diff --git a/synapse/http/client.py b/synapse/http/client.py
index 9eba046bbf..4abb479ae3 100644
--- a/synapse/http/client.py
+++ b/synapse/http/client.py
@@ -18,7 +18,7 @@ from OpenSSL.SSL import VERIFY_NONE
 from synapse.api.errors import (
     CodeMessageException, MatrixCodeMessageException, SynapseError, Codes,
 )
-from synapse.util.logcontext import preserve_context_over_fn
+from synapse.util.logcontext import make_deferred_yieldable
 from synapse.util import logcontext
 import synapse.metrics
 from synapse.http.endpoint import SpiderEndpoint
@@ -114,43 +114,73 @@ class SimpleHttpClient(object):
             raise e
 
     @defer.inlineCallbacks
-    def post_urlencoded_get_json(self, uri, args={}):
+    def post_urlencoded_get_json(self, uri, args={}, headers=None):
+        """
+        Args:
+            uri (str):
+            args (dict[str, str|List[str]]): query params
+            headers (dict[str, List[str]]|None): If not None, a map from
+               header name to a list of values for that header
+
+        Returns:
+            Deferred[object]: parsed json
+        """
+
         # TODO: Do we ever want to log message contents?
         logger.debug("post_urlencoded_get_json args: %s", args)
 
         query_bytes = urllib.urlencode(encode_urlencode_args(args), True)
 
+        actual_headers = {
+            b"Content-Type": [b"application/x-www-form-urlencoded"],
+            b"User-Agent": [self.user_agent],
+        }
+        if headers:
+            actual_headers.update(headers)
+
         response = yield self.request(
             "POST",
             uri.encode("ascii"),
-            headers=Headers({
-                b"Content-Type": [b"application/x-www-form-urlencoded"],
-                b"User-Agent": [self.user_agent],
-            }),
+            headers=Headers(actual_headers),
             bodyProducer=FileBodyProducer(StringIO(query_bytes))
         )
 
-        body = yield preserve_context_over_fn(readBody, response)
+        body = yield make_deferred_yieldable(readBody(response))
 
         defer.returnValue(json.loads(body))
 
     @defer.inlineCallbacks
-    def post_json_get_json(self, uri, post_json):
+    def post_json_get_json(self, uri, post_json, headers=None):
+        """
+
+        Args:
+            uri (str):
+            post_json (object):
+            headers (dict[str, List[str]]|None): If not None, a map from
+               header name to a list of values for that header
+
+        Returns:
+            Deferred[object]: parsed json
+        """
         json_str = encode_canonical_json(post_json)
 
         logger.debug("HTTP POST %s -> %s", json_str, uri)
 
+        actual_headers = {
+            b"Content-Type": [b"application/json"],
+            b"User-Agent": [self.user_agent],
+        }
+        if headers:
+            actual_headers.update(headers)
+
         response = yield self.request(
             "POST",
             uri.encode("ascii"),
-            headers=Headers({
-                b"Content-Type": [b"application/json"],
-                b"User-Agent": [self.user_agent],
-            }),
+            headers=Headers(actual_headers),
             bodyProducer=FileBodyProducer(StringIO(json_str))
         )
 
-        body = yield preserve_context_over_fn(readBody, response)
+        body = yield make_deferred_yieldable(readBody(response))
 
         if 200 <= response.code < 300:
             defer.returnValue(json.loads(body))
@@ -160,7 +190,7 @@ class SimpleHttpClient(object):
         defer.returnValue(json.loads(body))
 
     @defer.inlineCallbacks
-    def get_json(self, uri, args={}):
+    def get_json(self, uri, args={}, headers=None):
         """ Gets some json from the given URI.
 
         Args:
@@ -169,6 +199,8 @@ class SimpleHttpClient(object):
                 None.
                 **Note**: The value of each key is assumed to be an iterable
                 and *not* a string.
+            headers (dict[str, List[str]]|None): If not None, a map from
+               header name to a list of values for that header
         Returns:
             Deferred: Succeeds when we get *any* 2xx HTTP response, with the
             HTTP body as JSON.
@@ -177,13 +209,13 @@ class SimpleHttpClient(object):
             error message.
         """
         try:
-            body = yield self.get_raw(uri, args)
+            body = yield self.get_raw(uri, args, headers=headers)
             defer.returnValue(json.loads(body))
         except CodeMessageException as e:
             raise self._exceptionFromFailedRequest(e.code, e.msg)
 
     @defer.inlineCallbacks
-    def put_json(self, uri, json_body, args={}):
+    def put_json(self, uri, json_body, args={}, headers=None):
         """ Puts some json to the given URI.
 
         Args:
@@ -193,6 +225,8 @@ class SimpleHttpClient(object):
                 None.
                 **Note**: The value of each key is assumed to be an iterable
                 and *not* a string.
+            headers (dict[str, List[str]]|None): If not None, a map from
+               header name to a list of values for that header
         Returns:
             Deferred: Succeeds when we get *any* 2xx HTTP response, with the
             HTTP body as JSON.
@@ -205,17 +239,21 @@ class SimpleHttpClient(object):
 
         json_str = encode_canonical_json(json_body)
 
+        actual_headers = {
+            b"Content-Type": [b"application/json"],
+            b"User-Agent": [self.user_agent],
+        }
+        if headers:
+            actual_headers.update(headers)
+
         response = yield self.request(
             "PUT",
             uri.encode("ascii"),
-            headers=Headers({
-                b"User-Agent": [self.user_agent],
-                "Content-Type": ["application/json"]
-            }),
+            headers=Headers(actual_headers),
             bodyProducer=FileBodyProducer(StringIO(json_str))
         )
 
-        body = yield preserve_context_over_fn(readBody, response)
+        body = yield make_deferred_yieldable(readBody(response))
 
         if 200 <= response.code < 300:
             defer.returnValue(json.loads(body))
@@ -226,7 +264,7 @@ class SimpleHttpClient(object):
             raise CodeMessageException(response.code, body)
 
     @defer.inlineCallbacks
-    def get_raw(self, uri, args={}):
+    def get_raw(self, uri, args={}, headers=None):
         """ Gets raw text from the given URI.
 
         Args:
@@ -235,6 +273,8 @@ class SimpleHttpClient(object):
                 None.
                 **Note**: The value of each key is assumed to be an iterable
                 and *not* a string.
+            headers (dict[str, List[str]]|None): If not None, a map from
+               header name to a list of values for that header
         Returns:
             Deferred: Succeeds when we get *any* 2xx HTTP response, with the
             HTTP body at text.
@@ -246,15 +286,19 @@ class SimpleHttpClient(object):
             query_bytes = urllib.urlencode(args, True)
             uri = "%s?%s" % (uri, query_bytes)
 
+        actual_headers = {
+            b"User-Agent": [self.user_agent],
+        }
+        if headers:
+            actual_headers.update(headers)
+
         response = yield self.request(
             "GET",
             uri.encode("ascii"),
-            headers=Headers({
-                b"User-Agent": [self.user_agent],
-            })
+            headers=Headers(actual_headers),
         )
 
-        body = yield preserve_context_over_fn(readBody, response)
+        body = yield make_deferred_yieldable(readBody(response))
 
         if 200 <= response.code < 300:
             defer.returnValue(body)
@@ -274,27 +318,33 @@ class SimpleHttpClient(object):
     # The two should be factored out.
 
     @defer.inlineCallbacks
-    def get_file(self, url, output_stream, max_size=None):
+    def get_file(self, url, output_stream, max_size=None, headers=None):
         """GETs a file from a given URL
         Args:
             url (str): The URL to GET
             output_stream (file): File to write the response body to.
+            headers (dict[str, List[str]]|None): If not None, a map from
+               header name to a list of values for that header
         Returns:
             A (int,dict,string,int) tuple of the file length, dict of the response
             headers, absolute URI of the response and HTTP response code.
         """
 
+        actual_headers = {
+            b"User-Agent": [self.user_agent],
+        }
+        if headers:
+            actual_headers.update(headers)
+
         response = yield self.request(
             "GET",
             url.encode("ascii"),
-            headers=Headers({
-                b"User-Agent": [self.user_agent],
-            })
+            headers=Headers(actual_headers),
         )
 
-        headers = dict(response.headers.getAllRawHeaders())
+        resp_headers = dict(response.headers.getAllRawHeaders())
 
-        if 'Content-Length' in headers and headers['Content-Length'] > max_size:
+        if 'Content-Length' in resp_headers and resp_headers['Content-Length'] > max_size:
             logger.warn("Requested URL is too large > %r bytes" % (self.max_size,))
             raise SynapseError(
                 502,
@@ -315,10 +365,9 @@ class SimpleHttpClient(object):
         # straight back in again
 
         try:
-            length = yield preserve_context_over_fn(
-                _readBodyToFile,
-                response, output_stream, max_size
-            )
+            length = yield make_deferred_yieldable(_readBodyToFile(
+                response, output_stream, max_size,
+            ))
         except Exception as e:
             logger.exception("Failed to download body")
             raise SynapseError(
@@ -327,7 +376,9 @@ class SimpleHttpClient(object):
                 Codes.UNKNOWN,
             )
 
-        defer.returnValue((length, headers, response.request.absoluteURI, response.code))
+        defer.returnValue(
+            (length, resp_headers, response.request.absoluteURI, response.code),
+        )
 
 
 # XXX: FIXME: This is horribly copy-pasted from matrixfederationclient.
@@ -395,7 +446,7 @@ class CaptchaServerHttpClient(SimpleHttpClient):
         )
 
         try:
-            body = yield preserve_context_over_fn(readBody, response)
+            body = yield make_deferred_yieldable(readBody(response))
             defer.returnValue(body)
         except PartialDownloadError as e:
             # twisted dislikes google's response, no content length.
diff --git a/synapse/http/endpoint.py b/synapse/http/endpoint.py
index 241b17f2cb..e2b99ef3bd 100644
--- a/synapse/http/endpoint.py
+++ b/synapse/http/endpoint.py
@@ -354,16 +354,30 @@ def _get_hosts_for_srv_record(dns_client, host):
 
         return res[0]
 
-    def eb(res):
-        res.trap(DNSNameError)
-        return []
+    def eb(res, record_type):
+        if res.check(DNSNameError):
+            return []
+        logger.warn("Error looking up %s for %s: %s",
+                    record_type, host, res, res.value)
+        return res
 
     # no logcontexts here, so we can safely fire these off and gatherResults
-    d1 = dns_client.lookupAddress(host).addCallbacks(cb, eb)
-    d2 = dns_client.lookupIPV6Address(host).addCallbacks(cb, eb)
-    results = yield defer.gatherResults([d1, d2], consumeErrors=True)
+    d1 = dns_client.lookupAddress(host).addCallbacks(
+        cb, eb, errbackArgs=("A", ))
+    d2 = dns_client.lookupIPV6Address(host).addCallbacks(
+        cb, eb, errbackArgs=("AAAA", ))
+    results = yield defer.DeferredList(
+        [d1, d2], consumeErrors=True)
+
+    # if all of the lookups failed, raise an exception rather than blowing out
+    # the cache with an empty result.
+    if results and all(s == defer.FAILURE for (s, _) in results):
+        defer.returnValue(results[0][1])
+
+    for (success, result) in results:
+        if success == defer.FAILURE:
+            continue
 
-    for result in results:
         for answer in result:
             if not answer.payload:
                 continue
diff --git a/synapse/http/matrixfederationclient.py b/synapse/http/matrixfederationclient.py
index 747a791f83..833496b72d 100644
--- a/synapse/http/matrixfederationclient.py
+++ b/synapse/http/matrixfederationclient.py
@@ -204,18 +204,15 @@ class MatrixFederationHttpClient(object):
                             raise
 
                         logger.warn(
-                            "{%s} Sending request failed to %s: %s %s: %s - %s",
+                            "{%s} Sending request failed to %s: %s %s: %s",
                             txn_id,
                             destination,
                             method,
                             url_bytes,
-                            type(e).__name__,
                             _flatten_response_never_received(e),
                         )
 
-                        log_result = "%s - %s" % (
-                            type(e).__name__, _flatten_response_never_received(e),
-                        )
+                        log_result = _flatten_response_never_received(e)
 
                         if retries_left and not timeout:
                             if long_retries:
@@ -347,7 +344,7 @@ class MatrixFederationHttpClient(object):
 
     @defer.inlineCallbacks
     def post_json(self, destination, path, data={}, long_retries=False,
-                  timeout=None, ignore_backoff=False):
+                  timeout=None, ignore_backoff=False, args={}):
         """ Sends the specifed json data using POST
 
         Args:
@@ -383,6 +380,7 @@ class MatrixFederationHttpClient(object):
             destination,
             "POST",
             path,
+            query_bytes=encode_query_args(args),
             body_callback=body_callback,
             headers_dict={"Content-Type": ["application/json"]},
             long_retries=long_retries,
@@ -427,13 +425,6 @@ class MatrixFederationHttpClient(object):
         """
         logger.debug("get_json args: %s", args)
 
-        encoded_args = {}
-        for k, vs in args.items():
-            if isinstance(vs, basestring):
-                vs = [vs]
-            encoded_args[k] = [v.encode("UTF-8") for v in vs]
-
-        query_bytes = urllib.urlencode(encoded_args, True)
         logger.debug("Query bytes: %s Retry DNS: %s", args, retry_on_dns_fail)
 
         def body_callback(method, url_bytes, headers_dict):
@@ -444,7 +435,7 @@ class MatrixFederationHttpClient(object):
             destination,
             "GET",
             path,
-            query_bytes=query_bytes,
+            query_bytes=encode_query_args(args),
             body_callback=body_callback,
             retry_on_dns_fail=retry_on_dns_fail,
             timeout=timeout,
@@ -461,6 +452,52 @@ class MatrixFederationHttpClient(object):
         defer.returnValue(json.loads(body))
 
     @defer.inlineCallbacks
+    def delete_json(self, destination, path, long_retries=False,
+                    timeout=None, ignore_backoff=False, args={}):
+        """Send a DELETE request to the remote expecting some json response
+
+        Args:
+            destination (str): The remote server to send the HTTP request
+                to.
+            path (str): The HTTP path.
+            long_retries (bool): A boolean that indicates whether we should
+                retry for a short or long time.
+            timeout(int): How long to try (in ms) the destination for before
+                giving up. None indicates no timeout.
+            ignore_backoff (bool): true to ignore the historical backoff data and
+                try the request anyway.
+        Returns:
+            Deferred: Succeeds when we get a 2xx HTTP response. The result
+            will be the decoded JSON body.
+
+            Fails with ``HTTPRequestException`` if we get an HTTP response
+            code >= 300.
+
+            Fails with ``NotRetryingDestination`` if we are not yet ready
+            to retry this server.
+        """
+
+        response = yield self._request(
+            destination,
+            "DELETE",
+            path,
+            query_bytes=encode_query_args(args),
+            headers_dict={"Content-Type": ["application/json"]},
+            long_retries=long_retries,
+            timeout=timeout,
+            ignore_backoff=ignore_backoff,
+        )
+
+        if 200 <= response.code < 300:
+            # We need to update the transactions table to say it was sent?
+            check_content_type_is_json(response.headers)
+
+        with logcontext.PreserveLoggingContext():
+            body = yield readBody(response)
+
+        defer.returnValue(json.loads(body))
+
+    @defer.inlineCallbacks
     def get_file(self, destination, path, output_stream, args={},
                  retry_on_dns_fail=True, max_size=None,
                  ignore_backoff=False):
@@ -513,7 +550,7 @@ class MatrixFederationHttpClient(object):
                 length = yield _readBodyToFile(
                     response, output_stream, max_size
                 )
-        except:
+        except Exception:
             logger.exception("Failed to download body")
             raise
 
@@ -578,12 +615,14 @@ class _JsonProducer(object):
 
 def _flatten_response_never_received(e):
     if hasattr(e, "reasons"):
-        return ", ".join(
+        reasons = ", ".join(
             _flatten_response_never_received(f.value)
             for f in e.reasons
         )
+
+        return "%s:[%s]" % (type(e).__name__, reasons)
     else:
-        return "%s: %s" % (type(e).__name__, e.message,)
+        return repr(e)
 
 
 def check_content_type_is_json(headers):
@@ -610,3 +649,15 @@ def check_content_type_is_json(headers):
         raise RuntimeError(
             "Content-Type not application/json: was '%s'" % c_type
         )
+
+
+def encode_query_args(args):
+    encoded_args = {}
+    for k, vs in args.items():
+        if isinstance(vs, basestring):
+            vs = [vs]
+        encoded_args[k] = [v.encode("UTF-8") for v in vs]
+
+    query_bytes = urllib.urlencode(encoded_args, True)
+
+    return query_bytes
diff --git a/synapse/http/server.py b/synapse/http/server.py
index 7ef3d526b1..25466cd292 100644
--- a/synapse/http/server.py
+++ b/synapse/http/server.py
@@ -28,6 +28,7 @@ from canonicaljson import (
 )
 
 from twisted.internet import defer
+from twisted.python import failure
 from twisted.web import server, resource
 from twisted.web.server import NOT_DONE_YET
 from twisted.web.util import redirectTo
@@ -130,13 +131,18 @@ def wrap_request_handler(request_handler, include_metrics=False):
                             pretty_print=_request_user_agent_is_curl(request),
                             version_string=self.version_string,
                         )
-                    except:
-                        logger.exception(
-                            "Failed handle request %s.%s on %r: %r",
+                    except Exception:
+                        # failure.Failure() fishes the original Failure out
+                        # of our stack, and thus gives us a sensible stack
+                        # trace.
+                        f = failure.Failure()
+                        logger.error(
+                            "Failed handle request %s.%s on %r: %r: %s",
                             request_handler.__module__,
                             request_handler.__name__,
                             self,
-                            request
+                            request,
+                            f.getTraceback().rstrip(),
                         )
                         respond_with_json(
                             request,
@@ -145,7 +151,9 @@ def wrap_request_handler(request_handler, include_metrics=False):
                                 "error": "Internal server error",
                                 "errcode": Codes.UNKNOWN,
                             },
-                            send_cors=True
+                            send_cors=True,
+                            pretty_print=_request_user_agent_is_curl(request),
+                            version_string=self.version_string,
                         )
                     finally:
                         try:
diff --git a/synapse/http/servlet.py b/synapse/http/servlet.py
index 9a4c36ad5d..71420e54db 100644
--- a/synapse/http/servlet.py
+++ b/synapse/http/servlet.py
@@ -48,7 +48,7 @@ def parse_integer_from_args(args, name, default=None, required=False):
     if name in args:
         try:
             return int(args[name][0])
-        except:
+        except Exception:
             message = "Query parameter %r must be an integer" % (name,)
             raise SynapseError(400, message)
     else:
@@ -88,7 +88,7 @@ def parse_boolean_from_args(args, name, default=None, required=False):
                 "true": True,
                 "false": False,
             }[args[name][0]]
-        except:
+        except Exception:
             message = (
                 "Boolean query parameter %r must be one of"
                 " ['true', 'false']"
@@ -162,12 +162,13 @@ def parse_json_value_from_request(request):
     """
     try:
         content_bytes = request.content.read()
-    except:
+    except Exception:
         raise SynapseError(400, "Error reading JSON content.")
 
     try:
         content = simplejson.loads(content_bytes)
-    except simplejson.JSONDecodeError:
+    except Exception as e:
+        logger.warn("Unable to parse JSON: %s", e)
         raise SynapseError(400, "Content not JSON.", errcode=Codes.NOT_JSON)
 
     return content
diff --git a/synapse/http/site.py b/synapse/http/site.py
index 4b09d7ee66..cd1492b1c3 100644
--- a/synapse/http/site.py
+++ b/synapse/http/site.py
@@ -67,7 +67,7 @@ class SynapseRequest(Request):
             ru_utime, ru_stime = context.get_resource_usage()
             db_txn_count = context.db_txn_count
             db_txn_duration = context.db_txn_duration
-        except:
+        except Exception:
             ru_utime, ru_stime = (0, 0)
             db_txn_count, db_txn_duration = (0, 0)
 
diff --git a/synapse/module_api/__init__.py b/synapse/module_api/__init__.py
new file mode 100644
index 0000000000..097c844d31
--- /dev/null
+++ b/synapse/module_api/__init__.py
@@ -0,0 +1,123 @@
+# -*- coding: utf-8 -*-
+# Copyright 2017 New Vector Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+from twisted.internet import defer
+
+from synapse.types import UserID
+
+
+class ModuleApi(object):
+    """A proxy object that gets passed to password auth providers so they
+    can register new users etc if necessary.
+    """
+    def __init__(self, hs, auth_handler):
+        self.hs = hs
+
+        self._store = hs.get_datastore()
+        self._auth = hs.get_auth()
+        self._auth_handler = auth_handler
+
+    def get_user_by_req(self, req, allow_guest=False):
+        """Check the access_token provided for a request
+
+        Args:
+            req (twisted.web.server.Request): Incoming HTTP request
+            allow_guest (bool): True if guest users should be allowed. If this
+                is False, and the access token is for a guest user, an
+                AuthError will be thrown
+        Returns:
+            twisted.internet.defer.Deferred[synapse.types.Requester]:
+                the requester for this request
+        Raises:
+            synapse.api.errors.AuthError: if no user by that token exists,
+                or the token is invalid.
+        """
+        return self._auth.get_user_by_req(req, allow_guest)
+
+    def get_qualified_user_id(self, username):
+        """Qualify a user id, if necessary
+
+        Takes a user id provided by the user and adds the @ and :domain to
+        qualify it, if necessary
+
+        Args:
+            username (str): provided user id
+
+        Returns:
+            str: qualified @user:id
+        """
+        if username.startswith('@'):
+            return username
+        return UserID(username, self.hs.hostname).to_string()
+
+    def check_user_exists(self, user_id):
+        """Check if user exists.
+
+        Args:
+            user_id (str): Complete @user:id
+
+        Returns:
+            Deferred[str|None]: Canonical (case-corrected) user_id, or None
+               if the user is not registered.
+        """
+        return self._auth_handler.check_user_exists(user_id)
+
+    def register(self, localpart):
+        """Registers a new user with given localpart
+
+        Returns:
+            Deferred: a 2-tuple of (user_id, access_token)
+        """
+        reg = self.hs.get_handlers().registration_handler
+        return reg.register(localpart=localpart)
+
+    @defer.inlineCallbacks
+    def invalidate_access_token(self, access_token):
+        """Invalidate an access token for a user
+
+        Args:
+            access_token(str): access token
+
+        Returns:
+            twisted.internet.defer.Deferred - resolves once the access token
+               has been removed.
+
+        Raises:
+            synapse.api.errors.AuthError: the access token is invalid
+        """
+        # see if the access token corresponds to a device
+        user_info = yield self._auth.get_user_by_access_token(access_token)
+        device_id = user_info.get("device_id")
+        user_id = user_info["user"].to_string()
+        if device_id:
+            # delete the device, which will also delete its access tokens
+            yield self.hs.get_device_handler().delete_device(user_id, device_id)
+        else:
+            # no associated device. Just delete the access token.
+            yield self._auth_handler.delete_access_token(access_token)
+
+    def run_db_interaction(self, desc, func, *args, **kwargs):
+        """Run a function with a database connection
+
+        Args:
+            desc (str): description for the transaction, for metrics etc
+            func (func): function to be run. Passed a database cursor object
+                as well as *args and **kwargs
+            *args: positional args to be passed to func
+            **kwargs: named args to be passed to func
+
+        Returns:
+            Deferred[object]: result of func
+        """
+        return self._store.runInteraction(desc, func, *args, **kwargs)
diff --git a/synapse/notifier.py b/synapse/notifier.py
index 385208b574..ef042681bc 100644
--- a/synapse/notifier.py
+++ b/synapse/notifier.py
@@ -255,9 +255,7 @@ class Notifier(object):
         )
 
         if self.federation_sender:
-            preserve_fn(self.federation_sender.notify_new_events)(
-                room_stream_id
-            )
+            self.federation_sender.notify_new_events(room_stream_id)
 
         if event.type == EventTypes.Member and event.membership == Membership.JOIN:
             self._user_joined_room(event.state_key, event.room_id)
@@ -289,7 +287,7 @@ class Notifier(object):
                 for user_stream in user_streams:
                     try:
                         user_stream.notify(stream_key, new_token, time_now_ms)
-                    except:
+                    except Exception:
                         logger.exception("Failed to notify listener")
 
                 self.notify_replication()
@@ -297,8 +295,7 @@ class Notifier(object):
     def on_new_replication_data(self):
         """Used to inform replication listeners that something has happend
         without waking up any of the normal user event streams"""
-        with PreserveLoggingContext():
-            self.notify_replication()
+        self.notify_replication()
 
     @defer.inlineCallbacks
     def wait_for_events(self, user_id, timeout, callback, room_ids=None,
@@ -516,8 +513,14 @@ class Notifier(object):
             self.replication_deferred = ObservableDeferred(defer.Deferred())
             deferred.callback(None)
 
-        for cb in self.replication_callbacks:
-            preserve_fn(cb)()
+            # the callbacks may well outlast the current request, so we run
+            # them in the sentinel logcontext.
+            #
+            # (ideally it would be up to the callbacks to know if they were
+            # starting off background processes and drop the logcontext
+            # accordingly, but that requires more changes)
+            for cb in self.replication_callbacks:
+                cb()
 
     @defer.inlineCallbacks
     def wait_for_replication(self, callback, timeout):
diff --git a/synapse/push/baserules.py b/synapse/push/baserules.py
index 85effdfa46..7a18afe5f9 100644
--- a/synapse/push/baserules.py
+++ b/synapse/push/baserules.py
@@ -1,4 +1,5 @@
 # Copyright 2015, 2016 OpenMarket Ltd
+# Copyright 2017 New Vector Ltd
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -238,6 +239,28 @@ BASE_APPEND_OVERRIDE_RULES = [
             }
         ]
     },
+    {
+        'rule_id': 'global/override/.m.rule.roomnotif',
+        'conditions': [
+            {
+                'kind': 'event_match',
+                'key': 'content.body',
+                'pattern': '@room',
+                '_id': '_roomnotif_content',
+            },
+            {
+                'kind': 'sender_notification_permission',
+                'key': 'room',
+                '_id': '_roomnotif_pl',
+            },
+        ],
+        'actions': [
+            'notify', {
+                'set_tweak': 'highlight',
+                'value': True,
+            }
+        ]
+    }
 ]
 
 
diff --git a/synapse/push/bulk_push_rule_evaluator.py b/synapse/push/bulk_push_rule_evaluator.py
index b0d64aa6c4..425a017bdf 100644
--- a/synapse/push/bulk_push_rule_evaluator.py
+++ b/synapse/push/bulk_push_rule_evaluator.py
@@ -1,5 +1,6 @@
 # -*- coding: utf-8 -*-
 # Copyright 2015 OpenMarket Ltd
+# Copyright 2017 New Vector Ltd
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -19,11 +20,13 @@ from twisted.internet import defer
 
 from .push_rule_evaluator import PushRuleEvaluatorForEvent
 
+from synapse.event_auth import get_user_power_level
 from synapse.api.constants import EventTypes, Membership
 from synapse.metrics import get_metrics_for
 from synapse.util.caches import metrics as cache_metrics
 from synapse.util.caches.descriptors import cached
 from synapse.util.async import Linearizer
+from synapse.state import POWER_KEY
 
 from collections import namedtuple
 
@@ -59,6 +62,7 @@ class BulkPushRuleEvaluator(object):
     def __init__(self, hs):
         self.hs = hs
         self.store = hs.get_datastore()
+        self.auth = hs.get_auth()
 
         self.room_push_rule_cache_metrics = cache_metrics.register_cache(
             "cache",
@@ -109,6 +113,29 @@ class BulkPushRuleEvaluator(object):
         )
 
     @defer.inlineCallbacks
+    def _get_power_levels_and_sender_level(self, event, context):
+        pl_event_id = context.prev_state_ids.get(POWER_KEY)
+        if pl_event_id:
+            # fastpath: if there's a power level event, that's all we need, and
+            # not having a power level event is an extreme edge case
+            pl_event = yield self.store.get_event(pl_event_id)
+            auth_events = {POWER_KEY: pl_event}
+        else:
+            auth_events_ids = yield self.auth.compute_auth_events(
+                event, context.prev_state_ids, for_verification=False,
+            )
+            auth_events = yield self.store.get_events(auth_events_ids)
+            auth_events = {
+                (e.type, e.state_key): e for e in auth_events.itervalues()
+            }
+
+        sender_level = get_user_power_level(event.sender, auth_events)
+
+        pl_event = auth_events.get(POWER_KEY)
+
+        defer.returnValue((pl_event.content if pl_event else {}, sender_level))
+
+    @defer.inlineCallbacks
     def action_for_event_by_user(self, event, context):
         """Given an event and context, evaluate the push rules and return
         the results
@@ -123,7 +150,13 @@ class BulkPushRuleEvaluator(object):
             event, context
         )
 
-        evaluator = PushRuleEvaluatorForEvent(event, len(room_members))
+        (power_levels, sender_power_level) = (
+            yield self._get_power_levels_and_sender_level(event, context)
+        )
+
+        evaluator = PushRuleEvaluatorForEvent(
+            event, len(room_members), sender_power_level, power_levels,
+        )
 
         condition_cache = {}
 
diff --git a/synapse/push/emailpusher.py b/synapse/push/emailpusher.py
index a69dda7b09..58df98a793 100644
--- a/synapse/push/emailpusher.py
+++ b/synapse/push/emailpusher.py
@@ -121,7 +121,7 @@ class EmailPusher(object):
                         starting_max_ordering = self.max_stream_ordering
                         try:
                             yield self._unsafe_process()
-                        except:
+                        except Exception:
                             logger.exception("Exception processing notifs")
                         if self.max_stream_ordering == starting_max_ordering:
                             break
diff --git a/synapse/push/httppusher.py b/synapse/push/httppusher.py
index 62c41cd9db..c16f61452c 100644
--- a/synapse/push/httppusher.py
+++ b/synapse/push/httppusher.py
@@ -1,5 +1,6 @@
 # -*- coding: utf-8 -*-
 # Copyright 2015, 2016 OpenMarket Ltd
+# Copyright 2017 New Vector Ltd
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -131,7 +132,7 @@ class HttpPusher(object):
                         starting_max_ordering = self.max_stream_ordering
                         try:
                             yield self._unsafe_process()
-                        except:
+                        except Exception:
                             logger.exception("Exception processing notifs")
                         if self.max_stream_ordering == starting_max_ordering:
                             break
@@ -295,7 +296,7 @@ class HttpPusher(object):
         if event.type == 'm.room.member':
             d['notification']['membership'] = event.content['membership']
             d['notification']['user_is_target'] = event.state_key == self.user_id
-        if not self.hs.config.push_redact_content and 'content' in event:
+        if self.hs.config.push_include_content and 'content' in event:
             d['notification']['content'] = event.content
 
         # We no longer send aliases separately, instead, we send the human
@@ -314,7 +315,7 @@ class HttpPusher(object):
             defer.returnValue([])
         try:
             resp = yield self.http_client.post_json_get_json(self.url, notification_dict)
-        except:
+        except Exception:
             logger.warn("Failed to push %s ", self.url)
             defer.returnValue(False)
         rejected = []
@@ -345,7 +346,7 @@ class HttpPusher(object):
         }
         try:
             resp = yield self.http_client.post_json_get_json(self.url, d)
-        except:
+        except Exception:
             logger.exception("Failed to push %s ", self.url)
             defer.returnValue(False)
         rejected = []
diff --git a/synapse/push/push_rule_evaluator.py b/synapse/push/push_rule_evaluator.py
index 172c27c137..3601f2d365 100644
--- a/synapse/push/push_rule_evaluator.py
+++ b/synapse/push/push_rule_evaluator.py
@@ -1,5 +1,6 @@
 # -*- coding: utf-8 -*-
 # Copyright 2015, 2016 OpenMarket Ltd
+# Copyright 2017 New Vector Ltd
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -29,6 +30,21 @@ INEQUALITY_EXPR = re.compile("^([=<>]*)([0-9]*)$")
 
 
 def _room_member_count(ev, condition, room_member_count):
+    return _test_ineq_condition(condition, room_member_count)
+
+
+def _sender_notification_permission(ev, condition, sender_power_level, power_levels):
+    notif_level_key = condition.get('key')
+    if notif_level_key is None:
+        return False
+
+    notif_levels = power_levels.get('notifications', {})
+    room_notif_level = notif_levels.get(notif_level_key, 50)
+
+    return sender_power_level >= room_notif_level
+
+
+def _test_ineq_condition(condition, number):
     if 'is' not in condition:
         return False
     m = INEQUALITY_EXPR.match(condition['is'])
@@ -41,15 +57,15 @@ def _room_member_count(ev, condition, room_member_count):
     rhs = int(rhs)
 
     if ineq == '' or ineq == '==':
-        return room_member_count == rhs
+        return number == rhs
     elif ineq == '<':
-        return room_member_count < rhs
+        return number < rhs
     elif ineq == '>':
-        return room_member_count > rhs
+        return number > rhs
     elif ineq == '>=':
-        return room_member_count >= rhs
+        return number >= rhs
     elif ineq == '<=':
-        return room_member_count <= rhs
+        return number <= rhs
     else:
         return False
 
@@ -65,9 +81,11 @@ def tweaks_for_actions(actions):
 
 
 class PushRuleEvaluatorForEvent(object):
-    def __init__(self, event, room_member_count):
+    def __init__(self, event, room_member_count, sender_power_level, power_levels):
         self._event = event
         self._room_member_count = room_member_count
+        self._sender_power_level = sender_power_level
+        self._power_levels = power_levels
 
         # Maps strings of e.g. 'content.body' -> event["content"]["body"]
         self._value_cache = _flatten_dict(event)
@@ -81,6 +99,10 @@ class PushRuleEvaluatorForEvent(object):
             return _room_member_count(
                 self._event, condition, self._room_member_count
             )
+        elif condition['kind'] == 'sender_notification_permission':
+            return _sender_notification_permission(
+                self._event, condition, self._sender_power_level, self._power_levels,
+            )
         else:
             return True
 
@@ -183,7 +205,7 @@ def _glob_to_re(glob, word_boundary):
             r,
         )
         if word_boundary:
-            r = r"\b%s\b" % (r,)
+            r = _re_word_boundary(r)
 
             return re.compile(r, flags=re.IGNORECASE)
         else:
@@ -192,7 +214,7 @@ def _glob_to_re(glob, word_boundary):
             return re.compile(r, flags=re.IGNORECASE)
     elif word_boundary:
         r = re.escape(glob)
-        r = r"\b%s\b" % (r,)
+        r = _re_word_boundary(r)
 
         return re.compile(r, flags=re.IGNORECASE)
     else:
@@ -200,6 +222,18 @@ def _glob_to_re(glob, word_boundary):
         return re.compile(r, flags=re.IGNORECASE)
 
 
+def _re_word_boundary(r):
+    """
+    Adds word boundary characters to the start and end of an
+    expression to require that the match occur as a whole word,
+    but do so respecting the fact that strings starting or ending
+    with non-word characters will change word boundaries.
+    """
+    # we can't use \b as it chokes on unicode. however \W seems to be okay
+    # as shorthand for [^0-9A-Za-z_].
+    return r"(^|\W)%s(\W|$)" % (r,)
+
+
 def _flatten_dict(d, prefix=[], result=None):
     if result is None:
         result = {}
diff --git a/synapse/push/pusher.py b/synapse/push/pusher.py
index 491f27bded..71576330a9 100644
--- a/synapse/push/pusher.py
+++ b/synapse/push/pusher.py
@@ -27,7 +27,7 @@ logger = logging.getLogger(__name__)
 try:
     from synapse.push.emailpusher import EmailPusher
     from synapse.push.mailer import Mailer, load_jinja2_templates
-except:
+except Exception:
     pass
 
 
diff --git a/synapse/push/pusherpool.py b/synapse/push/pusherpool.py
index 43cb6e9c01..134e89b371 100644
--- a/synapse/push/pusherpool.py
+++ b/synapse/push/pusherpool.py
@@ -17,7 +17,7 @@
 from twisted.internet import defer
 
 from .pusher import PusherFactory
-from synapse.util.logcontext import preserve_fn, preserve_context_over_deferred
+from synapse.util.logcontext import make_deferred_yieldable, preserve_fn
 from synapse.util.async import run_on_reactor
 
 import logging
@@ -103,19 +103,25 @@ class PusherPool:
                 yield self.remove_pusher(p['app_id'], p['pushkey'], p['user_name'])
 
     @defer.inlineCallbacks
-    def remove_pushers_by_user(self, user_id, except_access_token_id=None):
-        all = yield self.store.get_all_pushers()
-        logger.info(
-            "Removing all pushers for user %s except access tokens id %r",
-            user_id, except_access_token_id
-        )
-        for p in all:
-            if p['user_name'] == user_id and p['access_token'] != except_access_token_id:
+    def remove_pushers_by_access_token(self, user_id, access_tokens):
+        """Remove the pushers for a given user corresponding to a set of
+        access_tokens.
+
+        Args:
+            user_id (str): user to remove pushers for
+            access_tokens (Iterable[int]): access token *ids* to remove pushers
+                for
+        """
+        tokens = set(access_tokens)
+        for p in (yield self.store.get_pushers_by_user_id(user_id)):
+            if p['access_token'] in tokens:
                 logger.info(
                     "Removing pusher for app id %s, pushkey %s, user %s",
                     p['app_id'], p['pushkey'], p['user_name']
                 )
-                yield self.remove_pusher(p['app_id'], p['pushkey'], p['user_name'])
+                yield self.remove_pusher(
+                    p['app_id'], p['pushkey'], p['user_name'],
+                )
 
     @defer.inlineCallbacks
     def on_new_notifications(self, min_stream_id, max_stream_id):
@@ -136,8 +142,8 @@ class PusherPool:
                             )
                         )
 
-            yield preserve_context_over_deferred(defer.gatherResults(deferreds))
-        except:
+            yield make_deferred_yieldable(defer.gatherResults(deferreds))
+        except Exception:
             logger.exception("Exception in pusher on_new_notifications")
 
     @defer.inlineCallbacks
@@ -161,8 +167,8 @@ class PusherPool:
                             preserve_fn(p.on_new_receipts)(min_stream_id, max_stream_id)
                         )
 
-            yield preserve_context_over_deferred(defer.gatherResults(deferreds))
-        except:
+            yield make_deferred_yieldable(defer.gatherResults(deferreds))
+        except Exception:
             logger.exception("Exception in pusher on_new_receipts")
 
     @defer.inlineCallbacks
@@ -188,7 +194,7 @@ class PusherPool:
         for pusherdict in pushers:
             try:
                 p = self.pusher_factory.create_pusher(pusherdict)
-            except:
+            except Exception:
                 logger.exception("Couldn't start a pusher: caught Exception")
                 continue
             if p:
diff --git a/synapse/python_dependencies.py b/synapse/python_dependencies.py
index 630e92c90e..7052333c19 100644
--- a/synapse/python_dependencies.py
+++ b/synapse/python_dependencies.py
@@ -40,7 +40,6 @@ REQUIREMENTS = {
     "pymacaroons-pynacl": ["pymacaroons"],
     "msgpack-python>=0.3.0": ["msgpack"],
     "phonenumbers>=8.2.0": ["phonenumbers"],
-    "affinity": ["affinity"],
 }
 CONDITIONAL_REQUIREMENTS = {
     "web_client": {
@@ -59,6 +58,9 @@ CONDITIONAL_REQUIREMENTS = {
     "psutil": {
         "psutil>=2.0.0": ["psutil>=2.0.0"],
     },
+    "affinity": {
+        "affinity": ["affinity"],
+    },
 }
 
 
diff --git a/synapse/replication/slave/storage/_base.py b/synapse/replication/slave/storage/_base.py
index b962641166..61f5590c53 100644
--- a/synapse/replication/slave/storage/_base.py
+++ b/synapse/replication/slave/storage/_base.py
@@ -25,7 +25,7 @@ logger = logging.getLogger(__name__)
 
 class BaseSlavedStore(SQLBaseStore):
     def __init__(self, db_conn, hs):
-        super(BaseSlavedStore, self).__init__(hs)
+        super(BaseSlavedStore, self).__init__(db_conn, hs)
         if isinstance(self.database_engine, PostgresEngine):
             self._cache_id_gen = SlavedIdTracker(
                 db_conn, "cache_invalidation_stream", "stream_id",
diff --git a/synapse/replication/slave/storage/events.py b/synapse/replication/slave/storage/events.py
index 94ebbffc1b..29d7296b43 100644
--- a/synapse/replication/slave/storage/events.py
+++ b/synapse/replication/slave/storage/events.py
@@ -12,20 +12,18 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-from ._base import BaseSlavedStore
-from ._slaved_id_tracker import SlavedIdTracker
+import logging
 
 from synapse.api.constants import EventTypes
 from synapse.storage import DataStore
-from synapse.storage.roommember import RoomMemberStore
 from synapse.storage.event_federation import EventFederationStore
 from synapse.storage.event_push_actions import EventPushActionsStore
-from synapse.storage.state import StateStore
+from synapse.storage.roommember import RoomMemberStore
+from synapse.storage.state import StateGroupReadStore
 from synapse.storage.stream import StreamStore
 from synapse.util.caches.stream_change_cache import StreamChangeCache
-
-import logging
-
+from ._base import BaseSlavedStore
+from ._slaved_id_tracker import SlavedIdTracker
 
 logger = logging.getLogger(__name__)
 
@@ -39,7 +37,7 @@ logger = logging.getLogger(__name__)
 # the method descriptor on the DataStore and chuck them into our class.
 
 
-class SlavedEventStore(BaseSlavedStore):
+class SlavedEventStore(StateGroupReadStore, BaseSlavedStore):
 
     def __init__(self, db_conn, hs):
         super(SlavedEventStore, self).__init__(db_conn, hs)
@@ -90,25 +88,9 @@ class SlavedEventStore(BaseSlavedStore):
     _get_unread_counts_by_pos_txn = (
         DataStore._get_unread_counts_by_pos_txn.__func__
     )
-    _get_state_group_for_events = (
-        StateStore.__dict__["_get_state_group_for_events"]
-    )
-    _get_state_group_for_event = (
-        StateStore.__dict__["_get_state_group_for_event"]
-    )
-    _get_state_groups_from_groups = (
-        StateStore.__dict__["_get_state_groups_from_groups"]
-    )
-    _get_state_groups_from_groups_txn = (
-        DataStore._get_state_groups_from_groups_txn.__func__
-    )
     get_recent_event_ids_for_room = (
         StreamStore.__dict__["get_recent_event_ids_for_room"]
     )
-    get_current_state_ids = (
-        StateStore.__dict__["get_current_state_ids"]
-    )
-    get_state_group_delta = StateStore.__dict__["get_state_group_delta"]
     _get_joined_hosts_cache = RoomMemberStore.__dict__["_get_joined_hosts_cache"]
     has_room_changed_since = DataStore.has_room_changed_since.__func__
 
@@ -134,12 +116,6 @@ class SlavedEventStore(BaseSlavedStore):
         DataStore.get_room_events_stream_for_room.__func__
     )
     get_events_around = DataStore.get_events_around.__func__
-    get_state_for_event = DataStore.get_state_for_event.__func__
-    get_state_for_events = DataStore.get_state_for_events.__func__
-    get_state_groups = DataStore.get_state_groups.__func__
-    get_state_groups_ids = DataStore.get_state_groups_ids.__func__
-    get_state_ids_for_event = DataStore.get_state_ids_for_event.__func__
-    get_state_ids_for_events = DataStore.get_state_ids_for_events.__func__
     get_joined_users_from_state = DataStore.get_joined_users_from_state.__func__
     get_joined_users_from_context = DataStore.get_joined_users_from_context.__func__
     _get_joined_users_from_context = (
@@ -169,10 +145,7 @@ class SlavedEventStore(BaseSlavedStore):
     _get_rooms_for_user_where_membership_is_txn = (
         DataStore._get_rooms_for_user_where_membership_is_txn.__func__
     )
-    _get_state_for_groups = DataStore._get_state_for_groups.__func__
-    _get_all_state_from_cache = DataStore._get_all_state_from_cache.__func__
     _get_events_around_txn = DataStore._get_events_around_txn.__func__
-    _get_some_state_from_cache = DataStore._get_some_state_from_cache.__func__
 
     get_backfill_events = DataStore.get_backfill_events.__func__
     _get_backfill_events = DataStore._get_backfill_events.__func__
diff --git a/synapse/replication/slave/storage/groups.py b/synapse/replication/slave/storage/groups.py
new file mode 100644
index 0000000000..0bc4bce5b0
--- /dev/null
+++ b/synapse/replication/slave/storage/groups.py
@@ -0,0 +1,54 @@
+# -*- coding: utf-8 -*-
+# Copyright 2016 OpenMarket Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from ._base import BaseSlavedStore
+from ._slaved_id_tracker import SlavedIdTracker
+from synapse.storage import DataStore
+from synapse.util.caches.stream_change_cache import StreamChangeCache
+
+
+class SlavedGroupServerStore(BaseSlavedStore):
+    def __init__(self, db_conn, hs):
+        super(SlavedGroupServerStore, self).__init__(db_conn, hs)
+
+        self.hs = hs
+
+        self._group_updates_id_gen = SlavedIdTracker(
+            db_conn, "local_group_updates", "stream_id",
+        )
+        self._group_updates_stream_cache = StreamChangeCache(
+            "_group_updates_stream_cache", self._group_updates_id_gen.get_current_token(),
+        )
+
+    get_groups_changes_for_user = DataStore.get_groups_changes_for_user.__func__
+    get_group_stream_token = DataStore.get_group_stream_token.__func__
+    get_all_groups_for_user = DataStore.get_all_groups_for_user.__func__
+
+    def stream_positions(self):
+        result = super(SlavedGroupServerStore, self).stream_positions()
+        result["groups"] = self._group_updates_id_gen.get_current_token()
+        return result
+
+    def process_replication_rows(self, stream_name, token, rows):
+        if stream_name == "groups":
+            self._group_updates_id_gen.advance(token)
+            for row in rows:
+                self._group_updates_stream_cache.entity_has_changed(
+                    row.user_id, token
+                )
+
+        return super(SlavedGroupServerStore, self).process_replication_rows(
+            stream_name, token, rows
+        )
diff --git a/synapse/replication/tcp/resource.py b/synapse/replication/tcp/resource.py
index 3ea3ca5a6f..786c3fe864 100644
--- a/synapse/replication/tcp/resource.py
+++ b/synapse/replication/tcp/resource.py
@@ -160,7 +160,11 @@ class ReplicationStreamer(object):
                             "Getting stream: %s: %s -> %s",
                             stream.NAME, stream.last_token, stream.upto_token
                         )
-                        updates, current_token = yield stream.get_updates()
+                        try:
+                            updates, current_token = yield stream.get_updates()
+                        except Exception:
+                            logger.info("Failed to handle stream %s", stream.NAME)
+                            raise
 
                         logger.debug(
                             "Sending %d updates to %d connections",
@@ -212,11 +216,12 @@ class ReplicationStreamer(object):
             self.federation_sender.federation_ack(token)
 
     @measure_func("repl.on_user_sync")
+    @defer.inlineCallbacks
     def on_user_sync(self, conn_id, user_id, is_syncing, last_sync_ms):
         """A client has started/stopped syncing on a worker.
         """
         user_sync_counter.inc()
-        self.presence_handler.update_external_syncs_row(
+        yield self.presence_handler.update_external_syncs_row(
             conn_id, user_id, is_syncing, last_sync_ms,
         )
 
@@ -240,11 +245,12 @@ class ReplicationStreamer(object):
         getattr(self.store, cache_func).invalidate(tuple(keys))
 
     @measure_func("repl.on_user_ip")
+    @defer.inlineCallbacks
     def on_user_ip(self, user_id, access_token, ip, user_agent, device_id, last_seen):
         """The client saw a user request
         """
         user_ip_cache_counter.inc()
-        self.store.insert_client_ip(
+        yield self.store.insert_client_ip(
             user_id, access_token, ip, user_agent, device_id, last_seen,
         )
 
diff --git a/synapse/replication/tcp/streams.py b/synapse/replication/tcp/streams.py
index fbafe12cc2..4c60bf79f9 100644
--- a/synapse/replication/tcp/streams.py
+++ b/synapse/replication/tcp/streams.py
@@ -118,6 +118,12 @@ CurrentStateDeltaStreamRow = namedtuple("CurrentStateDeltaStream", (
     "state_key",  # str
     "event_id",  # str, optional
 ))
+GroupsStreamRow = namedtuple("GroupsStreamRow", (
+    "group_id",  # str
+    "user_id",  # str
+    "type",  # str
+    "content",  # dict
+))
 
 
 class Stream(object):
@@ -464,6 +470,19 @@ class CurrentStateDeltaStream(Stream):
         super(CurrentStateDeltaStream, self).__init__(hs)
 
 
+class GroupServerStream(Stream):
+    NAME = "groups"
+    ROW_TYPE = GroupsStreamRow
+
+    def __init__(self, hs):
+        store = hs.get_datastore()
+
+        self.current_token = store.get_group_stream_token
+        self.update_function = store.get_all_groups_changes
+
+        super(GroupServerStream, self).__init__(hs)
+
+
 STREAMS_MAP = {
     stream.NAME: stream
     for stream in (
@@ -482,5 +501,6 @@ STREAMS_MAP = {
         TagAccountDataStream,
         AccountDataStream,
         CurrentStateDeltaStream,
+        GroupServerStream,
     )
 }
diff --git a/synapse/rest/__init__.py b/synapse/rest/__init__.py
index 3d809d181b..16f5a73b95 100644
--- a/synapse/rest/__init__.py
+++ b/synapse/rest/__init__.py
@@ -52,6 +52,7 @@ from synapse.rest.client.v2_alpha import (
     thirdparty,
     sendtodevice,
     user_directory,
+    groups,
 )
 
 from synapse.http.server import JsonResource
@@ -102,3 +103,4 @@ class ClientRestResource(JsonResource):
         thirdparty.register_servlets(hs, client_resource)
         sendtodevice.register_servlets(hs, client_resource)
         user_directory.register_servlets(hs, client_resource)
+        groups.register_servlets(hs, client_resource)
diff --git a/synapse/rest/client/v1/admin.py b/synapse/rest/client/v1/admin.py
index 465b25033d..5022808ea9 100644
--- a/synapse/rest/client/v1/admin.py
+++ b/synapse/rest/client/v1/admin.py
@@ -137,8 +137,8 @@ class DeactivateAccountRestServlet(ClientV1RestServlet):
     PATTERNS = client_path_patterns("/admin/deactivate/(?P<target_user_id>[^/]*)")
 
     def __init__(self, hs):
-        self.store = hs.get_datastore()
         super(DeactivateAccountRestServlet, self).__init__(hs)
+        self._deactivate_account_handler = hs.get_deactivate_account_handler()
 
     @defer.inlineCallbacks
     def on_POST(self, request, target_user_id):
@@ -149,12 +149,7 @@ class DeactivateAccountRestServlet(ClientV1RestServlet):
         if not is_admin:
             raise AuthError(403, "You are not a server admin")
 
-        # FIXME: Theoretically there is a race here wherein user resets password
-        # using threepid.
-        yield self.store.user_delete_access_tokens(target_user_id)
-        yield self.store.user_delete_threepids(target_user_id)
-        yield self.store.user_set_password_hash(target_user_id, None)
-
+        yield self._deactivate_account_handler.deactivate_account(target_user_id)
         defer.returnValue((200, {}))
 
 
@@ -314,7 +309,7 @@ class ResetPasswordRestServlet(ClientV1RestServlet):
         super(ResetPasswordRestServlet, self).__init__(hs)
         self.hs = hs
         self.auth = hs.get_auth()
-        self.auth_handler = hs.get_auth_handler()
+        self._set_password_handler = hs.get_set_password_handler()
 
     @defer.inlineCallbacks
     def on_POST(self, request, target_user_id):
@@ -335,7 +330,7 @@ class ResetPasswordRestServlet(ClientV1RestServlet):
 
         logger.info("new_password: %r", new_password)
 
-        yield self.auth_handler.set_password(
+        yield self._set_password_handler.set_password(
             target_user_id, new_password, requester
         )
         defer.returnValue((200, {}))
diff --git a/synapse/rest/client/v1/directory.py b/synapse/rest/client/v1/directory.py
index f15aa5c13f..1c3933380f 100644
--- a/synapse/rest/client/v1/directory.py
+++ b/synapse/rest/client/v1/directory.py
@@ -93,7 +93,7 @@ class ClientDirectoryServer(ClientV1RestServlet):
                 )
             except SynapseError as e:
                 raise e
-            except:
+            except Exception:
                 logger.exception("Failed to create association")
                 raise
         except AuthError:
diff --git a/synapse/rest/client/v1/login.py b/synapse/rest/client/v1/login.py
index a43410fb37..5669ecb724 100644
--- a/synapse/rest/client/v1/login.py
+++ b/synapse/rest/client/v1/login.py
@@ -85,7 +85,6 @@ def login_id_thirdparty_from_phone(identifier):
 
 class LoginRestServlet(ClientV1RestServlet):
     PATTERNS = client_path_patterns("/login$")
-    PASS_TYPE = "m.login.password"
     SAML2_TYPE = "m.login.saml2"
     CAS_TYPE = "m.login.cas"
     TOKEN_TYPE = "m.login.token"
@@ -94,7 +93,6 @@ class LoginRestServlet(ClientV1RestServlet):
     def __init__(self, hs):
         super(LoginRestServlet, self).__init__(hs)
         self.idp_redirect_url = hs.config.saml2_idp_redirect_url
-        self.password_enabled = hs.config.password_enabled
         self.saml2_enabled = hs.config.saml2_enabled
         self.jwt_enabled = hs.config.jwt_enabled
         self.jwt_secret = hs.config.jwt_secret
@@ -121,8 +119,10 @@ class LoginRestServlet(ClientV1RestServlet):
             # fall back to the fallback API if they don't understand one of the
             # login flow types returned.
             flows.append({"type": LoginRestServlet.TOKEN_TYPE})
-        if self.password_enabled:
-            flows.append({"type": LoginRestServlet.PASS_TYPE})
+
+        flows.extend((
+            {"type": t} for t in self.auth_handler.get_supported_login_types()
+        ))
 
         return (200, {"flows": flows})
 
@@ -133,14 +133,8 @@ class LoginRestServlet(ClientV1RestServlet):
     def on_POST(self, request):
         login_submission = parse_json_object_from_request(request)
         try:
-            if login_submission["type"] == LoginRestServlet.PASS_TYPE:
-                if not self.password_enabled:
-                    raise SynapseError(400, "Password login has been disabled.")
-
-                result = yield self.do_password_login(login_submission)
-                defer.returnValue(result)
-            elif self.saml2_enabled and (login_submission["type"] ==
-                                         LoginRestServlet.SAML2_TYPE):
+            if self.saml2_enabled and (login_submission["type"] ==
+                                       LoginRestServlet.SAML2_TYPE):
                 relay_state = ""
                 if "relay_state" in login_submission:
                     relay_state = "&RelayState=" + urllib.quote(
@@ -157,15 +151,31 @@ class LoginRestServlet(ClientV1RestServlet):
                 result = yield self.do_token_login(login_submission)
                 defer.returnValue(result)
             else:
-                raise SynapseError(400, "Bad login type.")
+                result = yield self._do_other_login(login_submission)
+                defer.returnValue(result)
         except KeyError:
             raise SynapseError(400, "Missing JSON keys.")
 
     @defer.inlineCallbacks
-    def do_password_login(self, login_submission):
-        if "password" not in login_submission:
-            raise SynapseError(400, "Missing parameter: password")
+    def _do_other_login(self, login_submission):
+        """Handle non-token/saml/jwt logins
 
+        Args:
+            login_submission:
+
+        Returns:
+            (int, object): HTTP code/response
+        """
+        # Log the request we got, but only certain fields to minimise the chance of
+        # logging someone's password (even if they accidentally put it in the wrong
+        # field)
+        logger.info(
+            "Got login request with identifier: %r, medium: %r, address: %r, user: %r",
+            login_submission.get('identifier'),
+            login_submission.get('medium'),
+            login_submission.get('address'),
+            login_submission.get('user'),
+        )
         login_submission_legacy_convert(login_submission)
 
         if "identifier" not in login_submission:
@@ -208,30 +218,29 @@ class LoginRestServlet(ClientV1RestServlet):
         if "user" not in identifier:
             raise SynapseError(400, "User identifier is missing 'user' key")
 
-        user_id = identifier["user"]
-
-        if not user_id.startswith('@'):
-            user_id = UserID.create(
-                user_id, self.hs.hostname
-            ).to_string()
-
         auth_handler = self.auth_handler
-        user_id = yield auth_handler.validate_password_login(
-            user_id=user_id,
-            password=login_submission["password"],
+        canonical_user_id, callback = yield auth_handler.validate_login(
+            identifier["user"],
+            login_submission,
+        )
+
+        device_id = yield self._register_device(
+            canonical_user_id, login_submission,
         )
-        device_id = yield self._register_device(user_id, login_submission)
         access_token = yield auth_handler.get_access_token_for_user_id(
-            user_id, device_id,
-            login_submission.get("initial_device_display_name"),
+            canonical_user_id, device_id,
         )
+
         result = {
-            "user_id": user_id,  # may have changed
+            "user_id": canonical_user_id,
             "access_token": access_token,
             "home_server": self.hs.hostname,
             "device_id": device_id,
         }
 
+        if callback is not None:
+            yield callback(result)
+
         defer.returnValue((200, result))
 
     @defer.inlineCallbacks
@@ -244,7 +253,6 @@ class LoginRestServlet(ClientV1RestServlet):
         device_id = yield self._register_device(user_id, login_submission)
         access_token = yield auth_handler.get_access_token_for_user_id(
             user_id, device_id,
-            login_submission.get("initial_device_display_name"),
         )
         result = {
             "user_id": user_id,  # may have changed
@@ -278,7 +286,7 @@ class LoginRestServlet(ClientV1RestServlet):
         if user is None:
             raise LoginError(401, "Invalid JWT", errcode=Codes.UNAUTHORIZED)
 
-        user_id = UserID.create(user, self.hs.hostname).to_string()
+        user_id = UserID(user, self.hs.hostname).to_string()
         auth_handler = self.auth_handler
         registered_user_id = yield auth_handler.check_user_exists(user_id)
         if registered_user_id:
@@ -287,7 +295,6 @@ class LoginRestServlet(ClientV1RestServlet):
             )
             access_token = yield auth_handler.get_access_token_for_user_id(
                 registered_user_id, device_id,
-                login_submission.get("initial_device_display_name"),
             )
 
             result = {
@@ -444,7 +451,7 @@ class CasTicketServlet(ClientV1RestServlet):
                 if required_value != actual_value:
                     raise LoginError(401, "Unauthorized", errcode=Codes.UNAUTHORIZED)
 
-        user_id = UserID.create(user, self.hs.hostname).to_string()
+        user_id = UserID(user, self.hs.hostname).to_string()
         auth_handler = self.auth_handler
         registered_user_id = yield auth_handler.check_user_exists(user_id)
         if not registered_user_id:
diff --git a/synapse/rest/client/v1/logout.py b/synapse/rest/client/v1/logout.py
index 1358d0acab..ca49955935 100644
--- a/synapse/rest/client/v1/logout.py
+++ b/synapse/rest/client/v1/logout.py
@@ -16,6 +16,7 @@
 from twisted.internet import defer
 
 from synapse.api.auth import get_access_token_from_request
+from synapse.api.errors import AuthError
 
 from .base import ClientV1RestServlet, client_path_patterns
 
@@ -30,15 +31,30 @@ class LogoutRestServlet(ClientV1RestServlet):
 
     def __init__(self, hs):
         super(LogoutRestServlet, self).__init__(hs)
-        self.store = hs.get_datastore()
+        self._auth = hs.get_auth()
+        self._auth_handler = hs.get_auth_handler()
+        self._device_handler = hs.get_device_handler()
 
     def on_OPTIONS(self, request):
         return (200, {})
 
     @defer.inlineCallbacks
     def on_POST(self, request):
-        access_token = get_access_token_from_request(request)
-        yield self.store.delete_access_token(access_token)
+        try:
+            requester = yield self.auth.get_user_by_req(request)
+        except AuthError:
+            # this implies the access token has already been deleted.
+            pass
+        else:
+            if requester.device_id is None:
+                # the acccess token wasn't associated with a device.
+                # Just delete the access token
+                access_token = get_access_token_from_request(request)
+                yield self._auth_handler.delete_access_token(access_token)
+            else:
+                yield self._device_handler.delete_device(
+                    requester.user.to_string(), requester.device_id)
+
         defer.returnValue((200, {}))
 
 
@@ -47,8 +63,9 @@ class LogoutAllRestServlet(ClientV1RestServlet):
 
     def __init__(self, hs):
         super(LogoutAllRestServlet, self).__init__(hs)
-        self.store = hs.get_datastore()
         self.auth = hs.get_auth()
+        self._auth_handler = hs.get_auth_handler()
+        self._device_handler = hs.get_device_handler()
 
     def on_OPTIONS(self, request):
         return (200, {})
@@ -57,7 +74,13 @@ class LogoutAllRestServlet(ClientV1RestServlet):
     def on_POST(self, request):
         requester = yield self.auth.get_user_by_req(request)
         user_id = requester.user.to_string()
-        yield self.store.user_delete_access_tokens(user_id)
+
+        # first delete all of the user's devices
+        yield self._device_handler.delete_all_devices_for_user(user_id)
+
+        # .. and then delete any access tokens which weren't associated with
+        # devices.
+        yield self._auth_handler.delete_access_tokens_for_user(user_id)
         defer.returnValue((200, {}))
 
 
diff --git a/synapse/rest/client/v1/presence.py b/synapse/rest/client/v1/presence.py
index 47b2dc45e7..4a73813c58 100644
--- a/synapse/rest/client/v1/presence.py
+++ b/synapse/rest/client/v1/presence.py
@@ -78,7 +78,7 @@ class PresenceStatusRestServlet(ClientV1RestServlet):
                 raise KeyError()
         except SynapseError as e:
             raise e
-        except:
+        except Exception:
             raise SynapseError(400, "Unable to parse state")
 
         yield self.presence_handler.set_state(user, state)
diff --git a/synapse/rest/client/v1/profile.py b/synapse/rest/client/v1/profile.py
index 1a5045c9ec..e4e3611a14 100644
--- a/synapse/rest/client/v1/profile.py
+++ b/synapse/rest/client/v1/profile.py
@@ -26,13 +26,13 @@ class ProfileDisplaynameRestServlet(ClientV1RestServlet):
 
     def __init__(self, hs):
         super(ProfileDisplaynameRestServlet, self).__init__(hs)
-        self.handlers = hs.get_handlers()
+        self.profile_handler = hs.get_profile_handler()
 
     @defer.inlineCallbacks
     def on_GET(self, request, user_id):
         user = UserID.from_string(user_id)
 
-        displayname = yield self.handlers.profile_handler.get_displayname(
+        displayname = yield self.profile_handler.get_displayname(
             user,
         )
 
@@ -52,10 +52,10 @@ class ProfileDisplaynameRestServlet(ClientV1RestServlet):
 
         try:
             new_name = content["displayname"]
-        except:
+        except Exception:
             defer.returnValue((400, "Unable to parse name"))
 
-        yield self.handlers.profile_handler.set_displayname(
+        yield self.profile_handler.set_displayname(
             user, requester, new_name, is_admin)
 
         defer.returnValue((200, {}))
@@ -69,13 +69,13 @@ class ProfileAvatarURLRestServlet(ClientV1RestServlet):
 
     def __init__(self, hs):
         super(ProfileAvatarURLRestServlet, self).__init__(hs)
-        self.handlers = hs.get_handlers()
+        self.profile_handler = hs.get_profile_handler()
 
     @defer.inlineCallbacks
     def on_GET(self, request, user_id):
         user = UserID.from_string(user_id)
 
-        avatar_url = yield self.handlers.profile_handler.get_avatar_url(
+        avatar_url = yield self.profile_handler.get_avatar_url(
             user,
         )
 
@@ -94,10 +94,10 @@ class ProfileAvatarURLRestServlet(ClientV1RestServlet):
         content = parse_json_object_from_request(request)
         try:
             new_name = content["avatar_url"]
-        except:
+        except Exception:
             defer.returnValue((400, "Unable to parse name"))
 
-        yield self.handlers.profile_handler.set_avatar_url(
+        yield self.profile_handler.set_avatar_url(
             user, requester, new_name, is_admin)
 
         defer.returnValue((200, {}))
@@ -111,16 +111,16 @@ class ProfileRestServlet(ClientV1RestServlet):
 
     def __init__(self, hs):
         super(ProfileRestServlet, self).__init__(hs)
-        self.handlers = hs.get_handlers()
+        self.profile_handler = hs.get_profile_handler()
 
     @defer.inlineCallbacks
     def on_GET(self, request, user_id):
         user = UserID.from_string(user_id)
 
-        displayname = yield self.handlers.profile_handler.get_displayname(
+        displayname = yield self.profile_handler.get_displayname(
             user,
         )
-        avatar_url = yield self.handlers.profile_handler.get_avatar_url(
+        avatar_url = yield self.profile_handler.get_avatar_url(
             user,
         )
 
diff --git a/synapse/rest/client/v1/register.py b/synapse/rest/client/v1/register.py
index ecf7e311a9..32ed1d3ab2 100644
--- a/synapse/rest/client/v1/register.py
+++ b/synapse/rest/client/v1/register.py
@@ -359,7 +359,7 @@ class RegisterRestServlet(ClientV1RestServlet):
         if compare_digest(want_mac, got_mac):
             handler = self.handlers.registration_handler
             user_id, token = yield handler.register(
-                localpart=user,
+                localpart=user.lower(),
                 password=password,
                 admin=bool(admin),
             )
diff --git a/synapse/rest/client/v1/room.py b/synapse/rest/client/v1/room.py
index 4be0fee38d..75b735b47d 100644
--- a/synapse/rest/client/v1/room.py
+++ b/synapse/rest/client/v1/room.py
@@ -238,7 +238,7 @@ class JoinRoomAliasServlet(ClientV1RestServlet):
 
         try:
             content = parse_json_object_from_request(request)
-        except:
+        except Exception:
             # Turns out we used to ignore the body entirely, and some clients
             # cheekily send invalid bodies.
             content = {}
@@ -247,7 +247,7 @@ class JoinRoomAliasServlet(ClientV1RestServlet):
             room_id = room_identifier
             try:
                 remote_room_hosts = request.args["server_name"]
-            except:
+            except Exception:
                 remote_room_hosts = None
         elif RoomAlias.is_valid(room_identifier):
             handler = self.handlers.room_member_handler
@@ -403,10 +403,9 @@ class JoinedRoomMemberListRestServlet(ClientV1RestServlet):
     @defer.inlineCallbacks
     def on_GET(self, request, room_id):
         requester = yield self.auth.get_user_by_req(request)
-        user_id = requester.user.to_string()
 
         users_with_profile = yield self.message_handler.get_joined_members(
-            user_id, room_id,
+            requester, room_id,
         )
 
         defer.returnValue((200, {
@@ -588,7 +587,7 @@ class RoomMembershipRestServlet(ClientV1RestServlet):
 
         try:
             content = parse_json_object_from_request(request)
-        except:
+        except Exception:
             # Turns out we used to ignore the body entirely, and some clients
             # cheekily send invalid bodies.
             content = {}
diff --git a/synapse/rest/client/v2_alpha/_base.py b/synapse/rest/client/v2_alpha/_base.py
index 1f5bc24cc3..77434937ff 100644
--- a/synapse/rest/client/v2_alpha/_base.py
+++ b/synapse/rest/client/v2_alpha/_base.py
@@ -15,12 +15,13 @@
 
 """This module contains base REST classes for constructing client v1 servlets.
 """
-
-from synapse.api.urls import CLIENT_V2_ALPHA_PREFIX
+import logging
 import re
 
-import logging
+from twisted.internet import defer
 
+from synapse.api.errors import InteractiveAuthIncompleteError
+from synapse.api.urls import CLIENT_V2_ALPHA_PREFIX
 
 logger = logging.getLogger(__name__)
 
@@ -57,3 +58,37 @@ def set_timeline_upper_limit(filter_json, filter_timeline_limit):
         filter_json['room']['timeline']["limit"] = min(
             filter_json['room']['timeline']['limit'],
             filter_timeline_limit)
+
+
+def interactive_auth_handler(orig):
+    """Wraps an on_POST method to handle InteractiveAuthIncompleteErrors
+
+    Takes a on_POST method which returns a deferred (errcode, body) response
+    and adds exception handling to turn a InteractiveAuthIncompleteError into
+    a 401 response.
+
+    Normal usage is:
+
+    @interactive_auth_handler
+    @defer.inlineCallbacks
+    def on_POST(self, request):
+        # ...
+        yield self.auth_handler.check_auth
+            """
+    def wrapped(*args, **kwargs):
+        res = defer.maybeDeferred(orig, *args, **kwargs)
+        res.addErrback(_catch_incomplete_interactive_auth)
+        return res
+    return wrapped
+
+
+def _catch_incomplete_interactive_auth(f):
+    """helper for interactive_auth_handler
+
+    Catches InteractiveAuthIncompleteErrors and turns them into 401 responses
+
+    Args:
+        f (failure.Failure):
+    """
+    f.trap(InteractiveAuthIncompleteError)
+    return 401, f.value.result
diff --git a/synapse/rest/client/v2_alpha/account.py b/synapse/rest/client/v2_alpha/account.py
index 4990b22b9f..385a3ad2ec 100644
--- a/synapse/rest/client/v2_alpha/account.py
+++ b/synapse/rest/client/v2_alpha/account.py
@@ -13,21 +13,20 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
+import logging
 
 from twisted.internet import defer
 
+from synapse.api.auth import has_access_token
 from synapse.api.constants import LoginType
-from synapse.api.errors import LoginError, SynapseError, Codes
+from synapse.api.errors import Codes, SynapseError
 from synapse.http.servlet import (
-    RestServlet, parse_json_object_from_request, assert_params_in_request
+    RestServlet, assert_params_in_request,
+    parse_json_object_from_request,
 )
 from synapse.util.async import run_on_reactor
 from synapse.util.msisdn import phone_number_to_msisdn
-
-from ._base import client_v2_patterns
-
-import logging
-
+from ._base import client_v2_patterns, interactive_auth_handler
 
 logger = logging.getLogger(__name__)
 
@@ -99,56 +98,61 @@ class PasswordRestServlet(RestServlet):
         self.auth = hs.get_auth()
         self.auth_handler = hs.get_auth_handler()
         self.datastore = self.hs.get_datastore()
+        self._set_password_handler = hs.get_set_password_handler()
 
+    @interactive_auth_handler
     @defer.inlineCallbacks
     def on_POST(self, request):
-        yield run_on_reactor()
-
         body = parse_json_object_from_request(request)
 
-        authed, result, params, _ = yield self.auth_handler.check_auth([
-            [LoginType.PASSWORD],
-            [LoginType.EMAIL_IDENTITY],
-            [LoginType.MSISDN],
-        ], body, self.hs.get_ip_from_request(request))
-
-        if not authed:
-            defer.returnValue((401, result))
-
-        user_id = None
-        requester = None
-
-        if LoginType.PASSWORD in result:
-            # if using password, they should also be logged in
+        # there are two possibilities here. Either the user does not have an
+        # access token, and needs to do a password reset; or they have one and
+        # need to validate their identity.
+        #
+        # In the first case, we offer a couple of means of identifying
+        # themselves (email and msisdn, though it's unclear if msisdn actually
+        # works).
+        #
+        # In the second case, we require a password to confirm their identity.
+
+        if has_access_token(request):
             requester = yield self.auth.get_user_by_req(request)
-            user_id = requester.user.to_string()
-            if user_id != result[LoginType.PASSWORD]:
-                raise LoginError(400, "", Codes.UNKNOWN)
-        elif LoginType.EMAIL_IDENTITY in result:
-            threepid = result[LoginType.EMAIL_IDENTITY]
-            if 'medium' not in threepid or 'address' not in threepid:
-                raise SynapseError(500, "Malformed threepid")
-            if threepid['medium'] == 'email':
-                # For emails, transform the address to lowercase.
-                # We store all email addreses as lowercase in the DB.
-                # (See add_threepid in synapse/handlers/auth.py)
-                threepid['address'] = threepid['address'].lower()
-            # if using email, we must know about the email they're authing with!
-            threepid_user_id = yield self.datastore.get_user_id_by_threepid(
-                threepid['medium'], threepid['address']
+            params = yield self.auth_handler.validate_user_via_ui_auth(
+                requester, body, self.hs.get_ip_from_request(request),
             )
-            if not threepid_user_id:
-                raise SynapseError(404, "Email address not found", Codes.NOT_FOUND)
-            user_id = threepid_user_id
+            user_id = requester.user.to_string()
         else:
-            logger.error("Auth succeeded but no known type!", result.keys())
-            raise SynapseError(500, "", Codes.UNKNOWN)
+            requester = None
+            result, params, _ = yield self.auth_handler.check_auth(
+                [[LoginType.EMAIL_IDENTITY], [LoginType.MSISDN]],
+                body, self.hs.get_ip_from_request(request),
+            )
+
+            if LoginType.EMAIL_IDENTITY in result:
+                threepid = result[LoginType.EMAIL_IDENTITY]
+                if 'medium' not in threepid or 'address' not in threepid:
+                    raise SynapseError(500, "Malformed threepid")
+                if threepid['medium'] == 'email':
+                    # For emails, transform the address to lowercase.
+                    # We store all email addreses as lowercase in the DB.
+                    # (See add_threepid in synapse/handlers/auth.py)
+                    threepid['address'] = threepid['address'].lower()
+                # if using email, we must know about the email they're authing with!
+                threepid_user_id = yield self.datastore.get_user_id_by_threepid(
+                    threepid['medium'], threepid['address']
+                )
+                if not threepid_user_id:
+                    raise SynapseError(404, "Email address not found", Codes.NOT_FOUND)
+                user_id = threepid_user_id
+            else:
+                logger.error("Auth succeeded but no known type!", result.keys())
+                raise SynapseError(500, "", Codes.UNKNOWN)
 
         if 'new_password' not in params:
             raise SynapseError(400, "", Codes.MISSING_PARAM)
         new_password = params['new_password']
 
-        yield self.auth_handler.set_password(
+        yield self._set_password_handler.set_password(
             user_id, new_password, requester
         )
 
@@ -162,42 +166,32 @@ class DeactivateAccountRestServlet(RestServlet):
     PATTERNS = client_v2_patterns("/account/deactivate$")
 
     def __init__(self, hs):
+        super(DeactivateAccountRestServlet, self).__init__()
         self.hs = hs
-        self.store = hs.get_datastore()
         self.auth = hs.get_auth()
         self.auth_handler = hs.get_auth_handler()
-        super(DeactivateAccountRestServlet, self).__init__()
+        self._deactivate_account_handler = hs.get_deactivate_account_handler()
 
+    @interactive_auth_handler
     @defer.inlineCallbacks
     def on_POST(self, request):
         body = parse_json_object_from_request(request)
 
-        authed, result, params, _ = yield self.auth_handler.check_auth([
-            [LoginType.PASSWORD],
-        ], body, self.hs.get_ip_from_request(request))
-
-        if not authed:
-            defer.returnValue((401, result))
-
-        user_id = None
-        requester = None
-
-        if LoginType.PASSWORD in result:
-            # if using password, they should also be logged in
-            requester = yield self.auth.get_user_by_req(request)
-            user_id = requester.user.to_string()
-            if user_id != result[LoginType.PASSWORD]:
-                raise LoginError(400, "", Codes.UNKNOWN)
-        else:
-            logger.error("Auth succeeded but no known type!", result.keys())
-            raise SynapseError(500, "", Codes.UNKNOWN)
+        requester = yield self.auth.get_user_by_req(request)
 
-        # FIXME: Theoretically there is a race here wherein user resets password
-        # using threepid.
-        yield self.store.user_delete_access_tokens(user_id)
-        yield self.store.user_delete_threepids(user_id)
-        yield self.store.user_set_password_hash(user_id, None)
+        # allow ASes to dectivate their own users
+        if requester.app_service:
+            yield self._deactivate_account_handler.deactivate_account(
+                requester.user.to_string()
+            )
+            defer.returnValue((200, {}))
 
+        yield self.auth_handler.validate_user_via_ui_auth(
+            requester, body, self.hs.get_ip_from_request(request),
+        )
+        yield self._deactivate_account_handler.deactivate_account(
+            requester.user.to_string(),
+        )
         defer.returnValue((200, {}))
 
 
@@ -373,6 +367,20 @@ class ThreepidDeleteRestServlet(RestServlet):
         defer.returnValue((200, {}))
 
 
+class WhoamiRestServlet(RestServlet):
+    PATTERNS = client_v2_patterns("/account/whoami$")
+
+    def __init__(self, hs):
+        super(WhoamiRestServlet, self).__init__()
+        self.auth = hs.get_auth()
+
+    @defer.inlineCallbacks
+    def on_GET(self, request):
+        requester = yield self.auth.get_user_by_req(request)
+
+        defer.returnValue((200, {'user_id': requester.user.to_string()}))
+
+
 def register_servlets(hs, http_server):
     EmailPasswordRequestTokenRestServlet(hs).register(http_server)
     MsisdnPasswordRequestTokenRestServlet(hs).register(http_server)
@@ -382,3 +390,4 @@ def register_servlets(hs, http_server):
     MsisdnThreepidRequestTokenRestServlet(hs).register(http_server)
     ThreepidRestServlet(hs).register(http_server)
     ThreepidDeleteRestServlet(hs).register(http_server)
+    WhoamiRestServlet(hs).register(http_server)
diff --git a/synapse/rest/client/v2_alpha/devices.py b/synapse/rest/client/v2_alpha/devices.py
index b57ba95d24..35d58b367a 100644
--- a/synapse/rest/client/v2_alpha/devices.py
+++ b/synapse/rest/client/v2_alpha/devices.py
@@ -17,15 +17,15 @@ import logging
 
 from twisted.internet import defer
 
-from synapse.api import constants, errors
+from synapse.api import errors
 from synapse.http import servlet
-from ._base import client_v2_patterns
+from ._base import client_v2_patterns, interactive_auth_handler
 
 logger = logging.getLogger(__name__)
 
 
 class DevicesRestServlet(servlet.RestServlet):
-    PATTERNS = client_v2_patterns("/devices$", releases=[], v2_alpha=False)
+    PATTERNS = client_v2_patterns("/devices$", v2_alpha=False)
 
     def __init__(self, hs):
         """
@@ -51,7 +51,7 @@ class DeleteDevicesRestServlet(servlet.RestServlet):
     API for bulk deletion of devices. Accepts a JSON object with a devices
     key which lists the device_ids to delete. Requires user interactive auth.
     """
-    PATTERNS = client_v2_patterns("/delete_devices", releases=[], v2_alpha=False)
+    PATTERNS = client_v2_patterns("/delete_devices", v2_alpha=False)
 
     def __init__(self, hs):
         super(DeleteDevicesRestServlet, self).__init__()
@@ -60,8 +60,11 @@ class DeleteDevicesRestServlet(servlet.RestServlet):
         self.device_handler = hs.get_device_handler()
         self.auth_handler = hs.get_auth_handler()
 
+    @interactive_auth_handler
     @defer.inlineCallbacks
     def on_POST(self, request):
+        requester = yield self.auth.get_user_by_req(request)
+
         try:
             body = servlet.parse_json_object_from_request(request)
         except errors.SynapseError as e:
@@ -77,14 +80,10 @@ class DeleteDevicesRestServlet(servlet.RestServlet):
                 400, "No devices supplied", errcode=errors.Codes.MISSING_PARAM
             )
 
-        authed, result, params, _ = yield self.auth_handler.check_auth([
-            [constants.LoginType.PASSWORD],
-        ], body, self.hs.get_ip_from_request(request))
-
-        if not authed:
-            defer.returnValue((401, result))
+        yield self.auth_handler.validate_user_via_ui_auth(
+            requester, body, self.hs.get_ip_from_request(request),
+        )
 
-        requester = yield self.auth.get_user_by_req(request)
         yield self.device_handler.delete_devices(
             requester.user.to_string(),
             body['devices'],
@@ -93,8 +92,7 @@ class DeleteDevicesRestServlet(servlet.RestServlet):
 
 
 class DeviceRestServlet(servlet.RestServlet):
-    PATTERNS = client_v2_patterns("/devices/(?P<device_id>[^/]*)$",
-                                  releases=[], v2_alpha=False)
+    PATTERNS = client_v2_patterns("/devices/(?P<device_id>[^/]*)$", v2_alpha=False)
 
     def __init__(self, hs):
         """
@@ -116,8 +114,11 @@ class DeviceRestServlet(servlet.RestServlet):
         )
         defer.returnValue((200, device))
 
+    @interactive_auth_handler
     @defer.inlineCallbacks
     def on_DELETE(self, request, device_id):
+        requester = yield self.auth.get_user_by_req(request)
+
         try:
             body = servlet.parse_json_object_from_request(request)
 
@@ -129,17 +130,12 @@ class DeviceRestServlet(servlet.RestServlet):
             else:
                 raise
 
-        authed, result, params, _ = yield self.auth_handler.check_auth([
-            [constants.LoginType.PASSWORD],
-        ], body, self.hs.get_ip_from_request(request))
-
-        if not authed:
-            defer.returnValue((401, result))
+        yield self.auth_handler.validate_user_via_ui_auth(
+            requester, body, self.hs.get_ip_from_request(request),
+        )
 
-        requester = yield self.auth.get_user_by_req(request)
         yield self.device_handler.delete_device(
-            requester.user.to_string(),
-            device_id,
+            requester.user.to_string(), device_id,
         )
         defer.returnValue((200, {}))
 
diff --git a/synapse/rest/client/v2_alpha/filter.py b/synapse/rest/client/v2_alpha/filter.py
index d2b2fd66e6..1b9dc4528d 100644
--- a/synapse/rest/client/v2_alpha/filter.py
+++ b/synapse/rest/client/v2_alpha/filter.py
@@ -50,7 +50,7 @@ class GetFilterRestServlet(RestServlet):
 
         try:
             filter_id = int(filter_id)
-        except:
+        except Exception:
             raise SynapseError(400, "Invalid filter_id")
 
         try:
diff --git a/synapse/rest/client/v2_alpha/groups.py b/synapse/rest/client/v2_alpha/groups.py
new file mode 100644
index 0000000000..f762dbfa9a
--- /dev/null
+++ b/synapse/rest/client/v2_alpha/groups.py
@@ -0,0 +1,758 @@
+# -*- coding: utf-8 -*-
+# Copyright 2017 Vector Creations Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from twisted.internet import defer
+
+from synapse.http.servlet import RestServlet, parse_json_object_from_request
+from synapse.types import GroupID
+
+from ._base import client_v2_patterns
+
+import logging
+
+logger = logging.getLogger(__name__)
+
+
+class GroupServlet(RestServlet):
+    """Get the group profile
+    """
+    PATTERNS = client_v2_patterns("/groups/(?P<group_id>[^/]*)/profile$")
+
+    def __init__(self, hs):
+        super(GroupServlet, self).__init__()
+        self.auth = hs.get_auth()
+        self.clock = hs.get_clock()
+        self.groups_handler = hs.get_groups_local_handler()
+
+    @defer.inlineCallbacks
+    def on_GET(self, request, group_id):
+        requester = yield self.auth.get_user_by_req(request, allow_guest=True)
+        requester_user_id = requester.user.to_string()
+
+        group_description = yield self.groups_handler.get_group_profile(
+            group_id,
+            requester_user_id,
+        )
+
+        defer.returnValue((200, group_description))
+
+    @defer.inlineCallbacks
+    def on_POST(self, request, group_id):
+        requester = yield self.auth.get_user_by_req(request)
+        requester_user_id = requester.user.to_string()
+
+        content = parse_json_object_from_request(request)
+        yield self.groups_handler.update_group_profile(
+            group_id, requester_user_id, content,
+        )
+
+        defer.returnValue((200, {}))
+
+
+class GroupSummaryServlet(RestServlet):
+    """Get the full group summary
+    """
+    PATTERNS = client_v2_patterns("/groups/(?P<group_id>[^/]*)/summary$")
+
+    def __init__(self, hs):
+        super(GroupSummaryServlet, self).__init__()
+        self.auth = hs.get_auth()
+        self.clock = hs.get_clock()
+        self.groups_handler = hs.get_groups_local_handler()
+
+    @defer.inlineCallbacks
+    def on_GET(self, request, group_id):
+        requester = yield self.auth.get_user_by_req(request, allow_guest=True)
+        requester_user_id = requester.user.to_string()
+
+        get_group_summary = yield self.groups_handler.get_group_summary(
+            group_id,
+            requester_user_id,
+        )
+
+        defer.returnValue((200, get_group_summary))
+
+
+class GroupSummaryRoomsCatServlet(RestServlet):
+    """Update/delete a rooms entry in the summary.
+
+    Matches both:
+        - /groups/:group/summary/rooms/:room_id
+        - /groups/:group/summary/categories/:category/rooms/:room_id
+    """
+    PATTERNS = client_v2_patterns(
+        "/groups/(?P<group_id>[^/]*)/summary"
+        "(/categories/(?P<category_id>[^/]+))?"
+        "/rooms/(?P<room_id>[^/]*)$"
+    )
+
+    def __init__(self, hs):
+        super(GroupSummaryRoomsCatServlet, self).__init__()
+        self.auth = hs.get_auth()
+        self.clock = hs.get_clock()
+        self.groups_handler = hs.get_groups_local_handler()
+
+    @defer.inlineCallbacks
+    def on_PUT(self, request, group_id, category_id, room_id):
+        requester = yield self.auth.get_user_by_req(request)
+        requester_user_id = requester.user.to_string()
+
+        content = parse_json_object_from_request(request)
+        resp = yield self.groups_handler.update_group_summary_room(
+            group_id, requester_user_id,
+            room_id=room_id,
+            category_id=category_id,
+            content=content,
+        )
+
+        defer.returnValue((200, resp))
+
+    @defer.inlineCallbacks
+    def on_DELETE(self, request, group_id, category_id, room_id):
+        requester = yield self.auth.get_user_by_req(request)
+        requester_user_id = requester.user.to_string()
+
+        resp = yield self.groups_handler.delete_group_summary_room(
+            group_id, requester_user_id,
+            room_id=room_id,
+            category_id=category_id,
+        )
+
+        defer.returnValue((200, resp))
+
+
+class GroupCategoryServlet(RestServlet):
+    """Get/add/update/delete a group category
+    """
+    PATTERNS = client_v2_patterns(
+        "/groups/(?P<group_id>[^/]*)/categories/(?P<category_id>[^/]+)$"
+    )
+
+    def __init__(self, hs):
+        super(GroupCategoryServlet, self).__init__()
+        self.auth = hs.get_auth()
+        self.clock = hs.get_clock()
+        self.groups_handler = hs.get_groups_local_handler()
+
+    @defer.inlineCallbacks
+    def on_GET(self, request, group_id, category_id):
+        requester = yield self.auth.get_user_by_req(request, allow_guest=True)
+        requester_user_id = requester.user.to_string()
+
+        category = yield self.groups_handler.get_group_category(
+            group_id, requester_user_id,
+            category_id=category_id,
+        )
+
+        defer.returnValue((200, category))
+
+    @defer.inlineCallbacks
+    def on_PUT(self, request, group_id, category_id):
+        requester = yield self.auth.get_user_by_req(request)
+        requester_user_id = requester.user.to_string()
+
+        content = parse_json_object_from_request(request)
+        resp = yield self.groups_handler.update_group_category(
+            group_id, requester_user_id,
+            category_id=category_id,
+            content=content,
+        )
+
+        defer.returnValue((200, resp))
+
+    @defer.inlineCallbacks
+    def on_DELETE(self, request, group_id, category_id):
+        requester = yield self.auth.get_user_by_req(request)
+        requester_user_id = requester.user.to_string()
+
+        resp = yield self.groups_handler.delete_group_category(
+            group_id, requester_user_id,
+            category_id=category_id,
+        )
+
+        defer.returnValue((200, resp))
+
+
+class GroupCategoriesServlet(RestServlet):
+    """Get all group categories
+    """
+    PATTERNS = client_v2_patterns(
+        "/groups/(?P<group_id>[^/]*)/categories/$"
+    )
+
+    def __init__(self, hs):
+        super(GroupCategoriesServlet, self).__init__()
+        self.auth = hs.get_auth()
+        self.clock = hs.get_clock()
+        self.groups_handler = hs.get_groups_local_handler()
+
+    @defer.inlineCallbacks
+    def on_GET(self, request, group_id):
+        requester = yield self.auth.get_user_by_req(request, allow_guest=True)
+        requester_user_id = requester.user.to_string()
+
+        category = yield self.groups_handler.get_group_categories(
+            group_id, requester_user_id,
+        )
+
+        defer.returnValue((200, category))
+
+
+class GroupRoleServlet(RestServlet):
+    """Get/add/update/delete a group role
+    """
+    PATTERNS = client_v2_patterns(
+        "/groups/(?P<group_id>[^/]*)/roles/(?P<role_id>[^/]+)$"
+    )
+
+    def __init__(self, hs):
+        super(GroupRoleServlet, self).__init__()
+        self.auth = hs.get_auth()
+        self.clock = hs.get_clock()
+        self.groups_handler = hs.get_groups_local_handler()
+
+    @defer.inlineCallbacks
+    def on_GET(self, request, group_id, role_id):
+        requester = yield self.auth.get_user_by_req(request, allow_guest=True)
+        requester_user_id = requester.user.to_string()
+
+        category = yield self.groups_handler.get_group_role(
+            group_id, requester_user_id,
+            role_id=role_id,
+        )
+
+        defer.returnValue((200, category))
+
+    @defer.inlineCallbacks
+    def on_PUT(self, request, group_id, role_id):
+        requester = yield self.auth.get_user_by_req(request)
+        requester_user_id = requester.user.to_string()
+
+        content = parse_json_object_from_request(request)
+        resp = yield self.groups_handler.update_group_role(
+            group_id, requester_user_id,
+            role_id=role_id,
+            content=content,
+        )
+
+        defer.returnValue((200, resp))
+
+    @defer.inlineCallbacks
+    def on_DELETE(self, request, group_id, role_id):
+        requester = yield self.auth.get_user_by_req(request)
+        requester_user_id = requester.user.to_string()
+
+        resp = yield self.groups_handler.delete_group_role(
+            group_id, requester_user_id,
+            role_id=role_id,
+        )
+
+        defer.returnValue((200, resp))
+
+
+class GroupRolesServlet(RestServlet):
+    """Get all group roles
+    """
+    PATTERNS = client_v2_patterns(
+        "/groups/(?P<group_id>[^/]*)/roles/$"
+    )
+
+    def __init__(self, hs):
+        super(GroupRolesServlet, self).__init__()
+        self.auth = hs.get_auth()
+        self.clock = hs.get_clock()
+        self.groups_handler = hs.get_groups_local_handler()
+
+    @defer.inlineCallbacks
+    def on_GET(self, request, group_id):
+        requester = yield self.auth.get_user_by_req(request, allow_guest=True)
+        requester_user_id = requester.user.to_string()
+
+        category = yield self.groups_handler.get_group_roles(
+            group_id, requester_user_id,
+        )
+
+        defer.returnValue((200, category))
+
+
+class GroupSummaryUsersRoleServlet(RestServlet):
+    """Update/delete a user's entry in the summary.
+
+    Matches both:
+        - /groups/:group/summary/users/:room_id
+        - /groups/:group/summary/roles/:role/users/:user_id
+    """
+    PATTERNS = client_v2_patterns(
+        "/groups/(?P<group_id>[^/]*)/summary"
+        "(/roles/(?P<role_id>[^/]+))?"
+        "/users/(?P<user_id>[^/]*)$"
+    )
+
+    def __init__(self, hs):
+        super(GroupSummaryUsersRoleServlet, self).__init__()
+        self.auth = hs.get_auth()
+        self.clock = hs.get_clock()
+        self.groups_handler = hs.get_groups_local_handler()
+
+    @defer.inlineCallbacks
+    def on_PUT(self, request, group_id, role_id, user_id):
+        requester = yield self.auth.get_user_by_req(request)
+        requester_user_id = requester.user.to_string()
+
+        content = parse_json_object_from_request(request)
+        resp = yield self.groups_handler.update_group_summary_user(
+            group_id, requester_user_id,
+            user_id=user_id,
+            role_id=role_id,
+            content=content,
+        )
+
+        defer.returnValue((200, resp))
+
+    @defer.inlineCallbacks
+    def on_DELETE(self, request, group_id, role_id, user_id):
+        requester = yield self.auth.get_user_by_req(request)
+        requester_user_id = requester.user.to_string()
+
+        resp = yield self.groups_handler.delete_group_summary_user(
+            group_id, requester_user_id,
+            user_id=user_id,
+            role_id=role_id,
+        )
+
+        defer.returnValue((200, resp))
+
+
+class GroupRoomServlet(RestServlet):
+    """Get all rooms in a group
+    """
+    PATTERNS = client_v2_patterns("/groups/(?P<group_id>[^/]*)/rooms$")
+
+    def __init__(self, hs):
+        super(GroupRoomServlet, self).__init__()
+        self.auth = hs.get_auth()
+        self.clock = hs.get_clock()
+        self.groups_handler = hs.get_groups_local_handler()
+
+    @defer.inlineCallbacks
+    def on_GET(self, request, group_id):
+        requester = yield self.auth.get_user_by_req(request, allow_guest=True)
+        requester_user_id = requester.user.to_string()
+
+        result = yield self.groups_handler.get_rooms_in_group(group_id, requester_user_id)
+
+        defer.returnValue((200, result))
+
+
+class GroupUsersServlet(RestServlet):
+    """Get all users in a group
+    """
+    PATTERNS = client_v2_patterns("/groups/(?P<group_id>[^/]*)/users$")
+
+    def __init__(self, hs):
+        super(GroupUsersServlet, self).__init__()
+        self.auth = hs.get_auth()
+        self.clock = hs.get_clock()
+        self.groups_handler = hs.get_groups_local_handler()
+
+    @defer.inlineCallbacks
+    def on_GET(self, request, group_id):
+        requester = yield self.auth.get_user_by_req(request, allow_guest=True)
+        requester_user_id = requester.user.to_string()
+
+        result = yield self.groups_handler.get_users_in_group(group_id, requester_user_id)
+
+        defer.returnValue((200, result))
+
+
+class GroupInvitedUsersServlet(RestServlet):
+    """Get users invited to a group
+    """
+    PATTERNS = client_v2_patterns("/groups/(?P<group_id>[^/]*)/invited_users$")
+
+    def __init__(self, hs):
+        super(GroupInvitedUsersServlet, self).__init__()
+        self.auth = hs.get_auth()
+        self.clock = hs.get_clock()
+        self.groups_handler = hs.get_groups_local_handler()
+
+    @defer.inlineCallbacks
+    def on_GET(self, request, group_id):
+        requester = yield self.auth.get_user_by_req(request)
+        requester_user_id = requester.user.to_string()
+
+        result = yield self.groups_handler.get_invited_users_in_group(
+            group_id,
+            requester_user_id,
+        )
+
+        defer.returnValue((200, result))
+
+
+class GroupCreateServlet(RestServlet):
+    """Create a group
+    """
+    PATTERNS = client_v2_patterns("/create_group$")
+
+    def __init__(self, hs):
+        super(GroupCreateServlet, self).__init__()
+        self.auth = hs.get_auth()
+        self.clock = hs.get_clock()
+        self.groups_handler = hs.get_groups_local_handler()
+        self.server_name = hs.hostname
+
+    @defer.inlineCallbacks
+    def on_POST(self, request):
+        requester = yield self.auth.get_user_by_req(request)
+        requester_user_id = requester.user.to_string()
+
+        # TODO: Create group on remote server
+        content = parse_json_object_from_request(request)
+        localpart = content.pop("localpart")
+        group_id = GroupID(localpart, self.server_name).to_string()
+
+        result = yield self.groups_handler.create_group(
+            group_id,
+            requester_user_id,
+            content,
+        )
+
+        defer.returnValue((200, result))
+
+
+class GroupAdminRoomsServlet(RestServlet):
+    """Add a room to the group
+    """
+    PATTERNS = client_v2_patterns(
+        "/groups/(?P<group_id>[^/]*)/admin/rooms/(?P<room_id>[^/]*)$"
+    )
+
+    def __init__(self, hs):
+        super(GroupAdminRoomsServlet, self).__init__()
+        self.auth = hs.get_auth()
+        self.clock = hs.get_clock()
+        self.groups_handler = hs.get_groups_local_handler()
+
+    @defer.inlineCallbacks
+    def on_PUT(self, request, group_id, room_id):
+        requester = yield self.auth.get_user_by_req(request)
+        requester_user_id = requester.user.to_string()
+
+        content = parse_json_object_from_request(request)
+        result = yield self.groups_handler.add_room_to_group(
+            group_id, requester_user_id, room_id, content,
+        )
+
+        defer.returnValue((200, result))
+
+    @defer.inlineCallbacks
+    def on_DELETE(self, request, group_id, room_id):
+        requester = yield self.auth.get_user_by_req(request)
+        requester_user_id = requester.user.to_string()
+
+        result = yield self.groups_handler.remove_room_from_group(
+            group_id, requester_user_id, room_id,
+        )
+
+        defer.returnValue((200, result))
+
+
+class GroupAdminRoomsConfigServlet(RestServlet):
+    """Update the config of a room in a group
+    """
+    PATTERNS = client_v2_patterns(
+        "/groups/(?P<group_id>[^/]*)/admin/rooms/(?P<room_id>[^/]*)"
+        "/config/(?P<config_key>[^/]*)$"
+    )
+
+    def __init__(self, hs):
+        super(GroupAdminRoomsConfigServlet, self).__init__()
+        self.auth = hs.get_auth()
+        self.clock = hs.get_clock()
+        self.groups_handler = hs.get_groups_local_handler()
+
+    @defer.inlineCallbacks
+    def on_PUT(self, request, group_id, room_id, config_key):
+        requester = yield self.auth.get_user_by_req(request)
+        requester_user_id = requester.user.to_string()
+
+        content = parse_json_object_from_request(request)
+        result = yield self.groups_handler.update_room_in_group(
+            group_id, requester_user_id, room_id, config_key, content,
+        )
+
+        defer.returnValue((200, result))
+
+
+class GroupAdminUsersInviteServlet(RestServlet):
+    """Invite a user to the group
+    """
+    PATTERNS = client_v2_patterns(
+        "/groups/(?P<group_id>[^/]*)/admin/users/invite/(?P<user_id>[^/]*)$"
+    )
+
+    def __init__(self, hs):
+        super(GroupAdminUsersInviteServlet, self).__init__()
+        self.auth = hs.get_auth()
+        self.clock = hs.get_clock()
+        self.groups_handler = hs.get_groups_local_handler()
+        self.store = hs.get_datastore()
+        self.is_mine_id = hs.is_mine_id
+
+    @defer.inlineCallbacks
+    def on_PUT(self, request, group_id, user_id):
+        requester = yield self.auth.get_user_by_req(request)
+        requester_user_id = requester.user.to_string()
+
+        content = parse_json_object_from_request(request)
+        config = content.get("config", {})
+        result = yield self.groups_handler.invite(
+            group_id, user_id, requester_user_id, config,
+        )
+
+        defer.returnValue((200, result))
+
+
+class GroupAdminUsersKickServlet(RestServlet):
+    """Kick a user from the group
+    """
+    PATTERNS = client_v2_patterns(
+        "/groups/(?P<group_id>[^/]*)/admin/users/remove/(?P<user_id>[^/]*)$"
+    )
+
+    def __init__(self, hs):
+        super(GroupAdminUsersKickServlet, self).__init__()
+        self.auth = hs.get_auth()
+        self.clock = hs.get_clock()
+        self.groups_handler = hs.get_groups_local_handler()
+
+    @defer.inlineCallbacks
+    def on_PUT(self, request, group_id, user_id):
+        requester = yield self.auth.get_user_by_req(request)
+        requester_user_id = requester.user.to_string()
+
+        content = parse_json_object_from_request(request)
+        result = yield self.groups_handler.remove_user_from_group(
+            group_id, user_id, requester_user_id, content,
+        )
+
+        defer.returnValue((200, result))
+
+
+class GroupSelfLeaveServlet(RestServlet):
+    """Leave a joined group
+    """
+    PATTERNS = client_v2_patterns(
+        "/groups/(?P<group_id>[^/]*)/self/leave$"
+    )
+
+    def __init__(self, hs):
+        super(GroupSelfLeaveServlet, self).__init__()
+        self.auth = hs.get_auth()
+        self.clock = hs.get_clock()
+        self.groups_handler = hs.get_groups_local_handler()
+
+    @defer.inlineCallbacks
+    def on_PUT(self, request, group_id):
+        requester = yield self.auth.get_user_by_req(request)
+        requester_user_id = requester.user.to_string()
+
+        content = parse_json_object_from_request(request)
+        result = yield self.groups_handler.remove_user_from_group(
+            group_id, requester_user_id, requester_user_id, content,
+        )
+
+        defer.returnValue((200, result))
+
+
+class GroupSelfJoinServlet(RestServlet):
+    """Attempt to join a group, or knock
+    """
+    PATTERNS = client_v2_patterns(
+        "/groups/(?P<group_id>[^/]*)/self/join$"
+    )
+
+    def __init__(self, hs):
+        super(GroupSelfJoinServlet, self).__init__()
+        self.auth = hs.get_auth()
+        self.clock = hs.get_clock()
+        self.groups_handler = hs.get_groups_local_handler()
+
+    @defer.inlineCallbacks
+    def on_PUT(self, request, group_id):
+        requester = yield self.auth.get_user_by_req(request)
+        requester_user_id = requester.user.to_string()
+
+        content = parse_json_object_from_request(request)
+        result = yield self.groups_handler.join_group(
+            group_id, requester_user_id, content,
+        )
+
+        defer.returnValue((200, result))
+
+
+class GroupSelfAcceptInviteServlet(RestServlet):
+    """Accept a group invite
+    """
+    PATTERNS = client_v2_patterns(
+        "/groups/(?P<group_id>[^/]*)/self/accept_invite$"
+    )
+
+    def __init__(self, hs):
+        super(GroupSelfAcceptInviteServlet, self).__init__()
+        self.auth = hs.get_auth()
+        self.clock = hs.get_clock()
+        self.groups_handler = hs.get_groups_local_handler()
+
+    @defer.inlineCallbacks
+    def on_PUT(self, request, group_id):
+        requester = yield self.auth.get_user_by_req(request)
+        requester_user_id = requester.user.to_string()
+
+        content = parse_json_object_from_request(request)
+        result = yield self.groups_handler.accept_invite(
+            group_id, requester_user_id, content,
+        )
+
+        defer.returnValue((200, result))
+
+
+class GroupSelfUpdatePublicityServlet(RestServlet):
+    """Update whether we publicise a users membership of a group
+    """
+    PATTERNS = client_v2_patterns(
+        "/groups/(?P<group_id>[^/]*)/self/update_publicity$"
+    )
+
+    def __init__(self, hs):
+        super(GroupSelfUpdatePublicityServlet, self).__init__()
+        self.auth = hs.get_auth()
+        self.clock = hs.get_clock()
+        self.store = hs.get_datastore()
+
+    @defer.inlineCallbacks
+    def on_PUT(self, request, group_id):
+        requester = yield self.auth.get_user_by_req(request)
+        requester_user_id = requester.user.to_string()
+
+        content = parse_json_object_from_request(request)
+        publicise = content["publicise"]
+        yield self.store.update_group_publicity(
+            group_id, requester_user_id, publicise,
+        )
+
+        defer.returnValue((200, {}))
+
+
+class PublicisedGroupsForUserServlet(RestServlet):
+    """Get the list of groups a user is advertising
+    """
+    PATTERNS = client_v2_patterns(
+        "/publicised_groups/(?P<user_id>[^/]*)$"
+    )
+
+    def __init__(self, hs):
+        super(PublicisedGroupsForUserServlet, self).__init__()
+        self.auth = hs.get_auth()
+        self.clock = hs.get_clock()
+        self.store = hs.get_datastore()
+        self.groups_handler = hs.get_groups_local_handler()
+
+    @defer.inlineCallbacks
+    def on_GET(self, request, user_id):
+        yield self.auth.get_user_by_req(request, allow_guest=True)
+
+        result = yield self.groups_handler.get_publicised_groups_for_user(
+            user_id
+        )
+
+        defer.returnValue((200, result))
+
+
+class PublicisedGroupsForUsersServlet(RestServlet):
+    """Get the list of groups a user is advertising
+    """
+    PATTERNS = client_v2_patterns(
+        "/publicised_groups$"
+    )
+
+    def __init__(self, hs):
+        super(PublicisedGroupsForUsersServlet, self).__init__()
+        self.auth = hs.get_auth()
+        self.clock = hs.get_clock()
+        self.store = hs.get_datastore()
+        self.groups_handler = hs.get_groups_local_handler()
+
+    @defer.inlineCallbacks
+    def on_POST(self, request):
+        yield self.auth.get_user_by_req(request, allow_guest=True)
+
+        content = parse_json_object_from_request(request)
+        user_ids = content["user_ids"]
+
+        result = yield self.groups_handler.bulk_get_publicised_groups(
+            user_ids
+        )
+
+        defer.returnValue((200, result))
+
+
+class GroupsForUserServlet(RestServlet):
+    """Get all groups the logged in user is joined to
+    """
+    PATTERNS = client_v2_patterns(
+        "/joined_groups$"
+    )
+
+    def __init__(self, hs):
+        super(GroupsForUserServlet, self).__init__()
+        self.auth = hs.get_auth()
+        self.clock = hs.get_clock()
+        self.groups_handler = hs.get_groups_local_handler()
+
+    @defer.inlineCallbacks
+    def on_GET(self, request):
+        requester = yield self.auth.get_user_by_req(request, allow_guest=True)
+        requester_user_id = requester.user.to_string()
+
+        result = yield self.groups_handler.get_joined_groups(requester_user_id)
+
+        defer.returnValue((200, result))
+
+
+def register_servlets(hs, http_server):
+    GroupServlet(hs).register(http_server)
+    GroupSummaryServlet(hs).register(http_server)
+    GroupInvitedUsersServlet(hs).register(http_server)
+    GroupUsersServlet(hs).register(http_server)
+    GroupRoomServlet(hs).register(http_server)
+    GroupCreateServlet(hs).register(http_server)
+    GroupAdminRoomsServlet(hs).register(http_server)
+    GroupAdminRoomsConfigServlet(hs).register(http_server)
+    GroupAdminUsersInviteServlet(hs).register(http_server)
+    GroupAdminUsersKickServlet(hs).register(http_server)
+    GroupSelfLeaveServlet(hs).register(http_server)
+    GroupSelfJoinServlet(hs).register(http_server)
+    GroupSelfAcceptInviteServlet(hs).register(http_server)
+    GroupsForUserServlet(hs).register(http_server)
+    GroupCategoryServlet(hs).register(http_server)
+    GroupCategoriesServlet(hs).register(http_server)
+    GroupSummaryRoomsCatServlet(hs).register(http_server)
+    GroupRoleServlet(hs).register(http_server)
+    GroupRolesServlet(hs).register(http_server)
+    GroupSelfUpdatePublicityServlet(hs).register(http_server)
+    GroupSummaryUsersRoleServlet(hs).register(http_server)
+    PublicisedGroupsForUserServlet(hs).register(http_server)
+    PublicisedGroupsForUsersServlet(hs).register(http_server)
diff --git a/synapse/rest/client/v2_alpha/keys.py b/synapse/rest/client/v2_alpha/keys.py
index 943e87e7fd..3cc87ea63f 100644
--- a/synapse/rest/client/v2_alpha/keys.py
+++ b/synapse/rest/client/v2_alpha/keys.py
@@ -53,8 +53,7 @@ class KeyUploadServlet(RestServlet):
       },
     }
     """
-    PATTERNS = client_v2_patterns("/keys/upload(/(?P<device_id>[^/]+))?$",
-                                  releases=())
+    PATTERNS = client_v2_patterns("/keys/upload(/(?P<device_id>[^/]+))?$")
 
     def __init__(self, hs):
         """
@@ -128,10 +127,7 @@ class KeyQueryServlet(RestServlet):
     } } } } } }
     """
 
-    PATTERNS = client_v2_patterns(
-        "/keys/query$",
-        releases=()
-    )
+    PATTERNS = client_v2_patterns("/keys/query$")
 
     def __init__(self, hs):
         """
@@ -160,10 +156,7 @@ class KeyChangesServlet(RestServlet):
         200 OK
         { "changed": ["@foo:example.com"] }
     """
-    PATTERNS = client_v2_patterns(
-        "/keys/changes$",
-        releases=()
-    )
+    PATTERNS = client_v2_patterns("/keys/changes$")
 
     def __init__(self, hs):
         """
@@ -213,10 +206,7 @@ class OneTimeKeyServlet(RestServlet):
     } } } }
 
     """
-    PATTERNS = client_v2_patterns(
-        "/keys/claim$",
-        releases=()
-    )
+    PATTERNS = client_v2_patterns("/keys/claim$")
 
     def __init__(self, hs):
         super(OneTimeKeyServlet, self).__init__()
diff --git a/synapse/rest/client/v2_alpha/notifications.py b/synapse/rest/client/v2_alpha/notifications.py
index fd2a3d69d4..ec170109fe 100644
--- a/synapse/rest/client/v2_alpha/notifications.py
+++ b/synapse/rest/client/v2_alpha/notifications.py
@@ -30,7 +30,7 @@ logger = logging.getLogger(__name__)
 
 
 class NotificationsServlet(RestServlet):
-    PATTERNS = client_v2_patterns("/notifications$", releases=())
+    PATTERNS = client_v2_patterns("/notifications$")
 
     def __init__(self, hs):
         super(NotificationsServlet, self).__init__()
diff --git a/synapse/rest/client/v2_alpha/register.py b/synapse/rest/client/v2_alpha/register.py
index 1421c18152..e9d88a8895 100644
--- a/synapse/rest/client/v2_alpha/register.py
+++ b/synapse/rest/client/v2_alpha/register.py
@@ -17,15 +17,17 @@
 from twisted.internet import defer
 
 import synapse
+import synapse.types
 from synapse.api.auth import get_access_token_from_request, has_access_token
 from synapse.api.constants import LoginType
+from synapse.types import RoomID, RoomAlias
 from synapse.api.errors import SynapseError, Codes, UnrecognizedRequestError
 from synapse.http.servlet import (
     RestServlet, parse_json_object_from_request, assert_params_in_request, parse_string
 )
 from synapse.util.msisdn import phone_number_to_msisdn
 
-from ._base import client_v2_patterns
+from ._base import client_v2_patterns, interactive_auth_handler
 
 import logging
 import hmac
@@ -170,9 +172,11 @@ class RegisterRestServlet(RestServlet):
         self.auth_handler = hs.get_auth_handler()
         self.registration_handler = hs.get_handlers().registration_handler
         self.identity_handler = hs.get_handlers().identity_handler
+        self.room_member_handler = hs.get_handlers().room_member_handler
         self.device_handler = hs.get_device_handler()
         self.macaroon_gen = hs.get_macaroon_generator()
 
+    @interactive_auth_handler
     @defer.inlineCallbacks
     def on_POST(self, request):
         yield run_on_reactor()
@@ -221,6 +225,12 @@ class RegisterRestServlet(RestServlet):
             # 'user' key not 'username'). Since this is a new addition, we'll
             # fallback to 'username' if they gave one.
             desired_username = body.get("user", desired_username)
+
+            # XXX we should check that desired_username is valid. Currently
+            # we give appservices carte blanche for any insanity in mxids,
+            # because the IRC bridges rely on being able to register stupid
+            # IDs.
+
             access_token = get_access_token_from_request(request)
 
             if isinstance(desired_username, basestring):
@@ -230,6 +240,15 @@ class RegisterRestServlet(RestServlet):
             defer.returnValue((200, result))  # we throw for non 200 responses
             return
 
+        # for either shared secret or regular registration, downcase the
+        # provided username before attempting to register it. This should mean
+        # that people who try to register with upper-case in their usernames
+        # don't get a nasty surprise. (Note that we treat username
+        # case-insenstively in login, so they are free to carry on imagining
+        # that their username is CrAzYh4cKeR if that keeps them happy)
+        if desired_username is not None:
+            desired_username = desired_username.lower()
+
         # == Shared Secret Registration == (e.g. create new user scripts)
         if 'mac' in body:
             # FIXME: Should we really be determining if this is shared secret
@@ -307,14 +326,10 @@ class RegisterRestServlet(RestServlet):
                     [LoginType.MSISDN, LoginType.EMAIL_IDENTITY],
                 ])
 
-        authed, auth_result, params, session_id = yield self.auth_handler.check_auth(
+        auth_result, params, session_id = yield self.auth_handler.check_auth(
             flows, body, self.hs.get_ip_from_request(request)
         )
 
-        if not authed:
-            defer.returnValue((401, auth_result))
-            return
-
         if registered_user_id is not None:
             logger.info(
                 "Already registered user ID %r for this session",
@@ -333,6 +348,9 @@ class RegisterRestServlet(RestServlet):
             new_password = params.get("password", None)
             guest_access_token = params.get("guest_access_token", None)
 
+            if desired_username is not None:
+                desired_username = desired_username.lower()
+
             (registered_user_id, _) = yield self.registration_handler.register(
                 localpart=desired_username,
                 password=new_password,
@@ -340,6 +358,14 @@ class RegisterRestServlet(RestServlet):
                 generate_token=False,
             )
 
+            # auto-join the user to any rooms we're supposed to dump them into
+            fake_requester = synapse.types.create_requester(registered_user_id)
+            for r in self.hs.config.auto_join_rooms:
+                try:
+                    yield self._join_user_to_room(fake_requester, r)
+                except Exception as e:
+                    logger.error("Failed to join new user to %r: %r", r, e)
+
             # remember that we've now registered that user account, and with
             #  what user ID (since the user may not have specified)
             self.auth_handler.set_session_data(
@@ -373,6 +399,29 @@ class RegisterRestServlet(RestServlet):
         return 200, {}
 
     @defer.inlineCallbacks
+    def _join_user_to_room(self, requester, room_identifier):
+        room_id = None
+        if RoomID.is_valid(room_identifier):
+            room_id = room_identifier
+        elif RoomAlias.is_valid(room_identifier):
+            room_alias = RoomAlias.from_string(room_identifier)
+            room_id, remote_room_hosts = (
+                yield self.room_member_handler.lookup_room_alias(room_alias)
+            )
+            room_id = room_id.to_string()
+        else:
+            raise SynapseError(400, "%s was not legal room ID or room alias" % (
+                room_identifier,
+            ))
+
+        yield self.room_member_handler.update_membership(
+            requester=requester,
+            target=requester.user,
+            room_id=room_id,
+            action="join",
+        )
+
+    @defer.inlineCallbacks
     def _do_appservice_registration(self, username, as_token, body):
         user_id = yield self.registration_handler.appservice_register(
             username, as_token
@@ -383,13 +432,22 @@ class RegisterRestServlet(RestServlet):
     def _do_shared_secret_registration(self, username, password, body):
         if not self.hs.config.registration_shared_secret:
             raise SynapseError(400, "Shared secret registration is not enabled")
+        if not username:
+            raise SynapseError(
+                400, "username must be specified", errcode=Codes.BAD_JSON,
+            )
 
-        user = username.encode("utf-8")
+        # use the username from the original request rather than the
+        # downcased one in `username` for the mac calculation
+        user = body["username"].encode("utf-8")
 
         # str() because otherwise hmac complains that 'unicode' does not
         # have the buffer interface
         got_mac = str(body["mac"])
 
+        # FIXME this is different to the /v1/register endpoint, which
+        # includes the password and admin flag in the hashed text. Why are
+        # these different?
         want_mac = hmac.new(
             key=self.hs.config.registration_shared_secret,
             msg=user,
@@ -523,25 +581,28 @@ class RegisterRestServlet(RestServlet):
         Args:
             (str) user_id: full canonical @user:id
             (object) params: registration parameters, from which we pull
-                device_id and initial_device_name
+                device_id, initial_device_name and inhibit_login
         Returns:
             defer.Deferred: (object) dictionary for response from /register
         """
-        device_id = yield self._register_device(user_id, params)
+        result = {
+            "user_id": user_id,
+            "home_server": self.hs.hostname,
+        }
+        if not params.get("inhibit_login", False):
+            device_id = yield self._register_device(user_id, params)
 
-        access_token = (
-            yield self.auth_handler.get_access_token_for_user_id(
-                user_id, device_id=device_id,
-                initial_display_name=params.get("initial_device_display_name")
+            access_token = (
+                yield self.auth_handler.get_access_token_for_user_id(
+                    user_id, device_id=device_id,
+                )
             )
-        )
 
-        defer.returnValue({
-            "user_id": user_id,
-            "access_token": access_token,
-            "home_server": self.hs.hostname,
-            "device_id": device_id,
-        })
+            result.update({
+                "access_token": access_token,
+                "device_id": device_id,
+            })
+        defer.returnValue(result)
 
     def _register_device(self, user_id, params):
         """Register a device for a user.
diff --git a/synapse/rest/client/v2_alpha/sendtodevice.py b/synapse/rest/client/v2_alpha/sendtodevice.py
index d607bd2970..90bdb1db15 100644
--- a/synapse/rest/client/v2_alpha/sendtodevice.py
+++ b/synapse/rest/client/v2_alpha/sendtodevice.py
@@ -29,7 +29,7 @@ logger = logging.getLogger(__name__)
 class SendToDeviceRestServlet(servlet.RestServlet):
     PATTERNS = client_v2_patterns(
         "/sendToDevice/(?P<message_type>[^/]*)/(?P<txn_id>[^/]*)$",
-        releases=[], v2_alpha=False
+        v2_alpha=False
     )
 
     def __init__(self, hs):
diff --git a/synapse/rest/client/v2_alpha/sync.py b/synapse/rest/client/v2_alpha/sync.py
index 978af9c280..a0a8e4b8e4 100644
--- a/synapse/rest/client/v2_alpha/sync.py
+++ b/synapse/rest/client/v2_alpha/sync.py
@@ -125,7 +125,7 @@ class SyncRestServlet(RestServlet):
                     filter_object = json.loads(filter_id)
                     set_timeline_upper_limit(filter_object,
                                              self.hs.config.filter_timeline_limit)
-                except:
+                except Exception:
                     raise SynapseError(400, "Invalid filter JSON")
                 self.filtering.check_valid_filter(filter_object)
                 filter = FilterCollection(filter_object)
@@ -200,6 +200,11 @@ class SyncRestServlet(RestServlet):
                 "invite": invited,
                 "leave": archived,
             },
+            "groups": {
+                "join": sync_result.groups.join,
+                "invite": sync_result.groups.invite,
+                "leave": sync_result.groups.leave,
+            },
             "device_one_time_keys_count": sync_result.device_one_time_keys_count,
             "next_batch": sync_result.next_batch.to_string(),
         }
diff --git a/synapse/rest/client/v2_alpha/thirdparty.py b/synapse/rest/client/v2_alpha/thirdparty.py
index 6fceb23e26..6773b9ba60 100644
--- a/synapse/rest/client/v2_alpha/thirdparty.py
+++ b/synapse/rest/client/v2_alpha/thirdparty.py
@@ -26,7 +26,7 @@ logger = logging.getLogger(__name__)
 
 
 class ThirdPartyProtocolsServlet(RestServlet):
-    PATTERNS = client_v2_patterns("/thirdparty/protocols", releases=())
+    PATTERNS = client_v2_patterns("/thirdparty/protocols")
 
     def __init__(self, hs):
         super(ThirdPartyProtocolsServlet, self).__init__()
@@ -43,8 +43,7 @@ class ThirdPartyProtocolsServlet(RestServlet):
 
 
 class ThirdPartyProtocolServlet(RestServlet):
-    PATTERNS = client_v2_patterns("/thirdparty/protocol/(?P<protocol>[^/]+)$",
-                                  releases=())
+    PATTERNS = client_v2_patterns("/thirdparty/protocol/(?P<protocol>[^/]+)$")
 
     def __init__(self, hs):
         super(ThirdPartyProtocolServlet, self).__init__()
@@ -66,8 +65,7 @@ class ThirdPartyProtocolServlet(RestServlet):
 
 
 class ThirdPartyUserServlet(RestServlet):
-    PATTERNS = client_v2_patterns("/thirdparty/user(/(?P<protocol>[^/]+))?$",
-                                  releases=())
+    PATTERNS = client_v2_patterns("/thirdparty/user(/(?P<protocol>[^/]+))?$")
 
     def __init__(self, hs):
         super(ThirdPartyUserServlet, self).__init__()
@@ -90,8 +88,7 @@ class ThirdPartyUserServlet(RestServlet):
 
 
 class ThirdPartyLocationServlet(RestServlet):
-    PATTERNS = client_v2_patterns("/thirdparty/location(/(?P<protocol>[^/]+))?$",
-                                  releases=())
+    PATTERNS = client_v2_patterns("/thirdparty/location(/(?P<protocol>[^/]+))?$")
 
     def __init__(self, hs):
         super(ThirdPartyLocationServlet, self).__init__()
diff --git a/synapse/rest/client/v2_alpha/user_directory.py b/synapse/rest/client/v2_alpha/user_directory.py
index 6e012da4aa..2d4a43c353 100644
--- a/synapse/rest/client/v2_alpha/user_directory.py
+++ b/synapse/rest/client/v2_alpha/user_directory.py
@@ -65,7 +65,7 @@ class UserDirectorySearchRestServlet(RestServlet):
 
         try:
             search_term = body["search_term"]
-        except:
+        except Exception:
             raise SynapseError(400, "`search_term` is required field")
 
         results = yield self.user_directory_handler.search_users(
diff --git a/synapse/rest/client/versions.py b/synapse/rest/client/versions.py
index e984ea47db..2ecb15deee 100644
--- a/synapse/rest/client/versions.py
+++ b/synapse/rest/client/versions.py
@@ -30,6 +30,7 @@ class VersionsRestServlet(RestServlet):
                 "r0.0.1",
                 "r0.1.0",
                 "r0.2.0",
+                "r0.3.0",
             ]
         })
 
diff --git a/synapse/rest/key/v2/remote_key_resource.py b/synapse/rest/key/v2/remote_key_resource.py
index 9fe2013657..cc2842aa72 100644
--- a/synapse/rest/key/v2/remote_key_resource.py
+++ b/synapse/rest/key/v2/remote_key_resource.py
@@ -213,7 +213,7 @@ class RemoteKey(Resource):
                     )
                 except KeyLookupError as e:
                     logger.info("Failed to fetch key: %s", e)
-                except:
+                except Exception:
                     logger.exception("Failed to get key for %r", server_name)
             yield self.query_keys(
                 request, query, query_remote_on_cache_miss=False
diff --git a/synapse/rest/media/v1/_base.py b/synapse/rest/media/v1/_base.py
index b9600f2167..95fa95fce3 100644
--- a/synapse/rest/media/v1/_base.py
+++ b/synapse/rest/media/v1/_base.py
@@ -17,6 +17,7 @@ from synapse.http.server import respond_with_json, finish_request
 from synapse.api.errors import (
     cs_error, Codes, SynapseError
 )
+from synapse.util import logcontext
 
 from twisted.internet import defer
 from twisted.protocols.basic import FileSender
@@ -44,7 +45,7 @@ def parse_media_id(request):
             except UnicodeDecodeError:
                 pass
         return server_name, media_id, file_name
-    except:
+    except Exception:
         raise SynapseError(
             404,
             "Invalid media id token %r" % (request.postpath,),
@@ -103,7 +104,9 @@ def respond_with_file(request, media_type, file_path,
         )
 
         with open(file_path, "rb") as f:
-            yield FileSender().beginFileTransfer(f, request)
+            yield logcontext.make_deferred_yieldable(
+                FileSender().beginFileTransfer(f, request)
+            )
 
         finish_request(request)
     else:
diff --git a/synapse/rest/media/v1/filepath.py b/synapse/rest/media/v1/filepath.py
index d92b7ff337..d5164e47e0 100644
--- a/synapse/rest/media/v1/filepath.py
+++ b/synapse/rest/media/v1/filepath.py
@@ -14,78 +14,200 @@
 # limitations under the License.
 
 import os
+import re
+import functools
+
+NEW_FORMAT_ID_RE = re.compile(r"^\d\d\d\d-\d\d-\d\d")
+
+
+def _wrap_in_base_path(func):
+    """Takes a function that returns a relative path and turns it into an
+    absolute path based on the location of the primary media store
+    """
+    @functools.wraps(func)
+    def _wrapped(self, *args, **kwargs):
+        path = func(self, *args, **kwargs)
+        return os.path.join(self.base_path, path)
+
+    return _wrapped
 
 
 class MediaFilePaths(object):
+    """Describes where files are stored on disk.
 
-    def __init__(self, base_path):
-        self.base_path = base_path
+    Most of the functions have a `*_rel` variant which returns a file path that
+    is relative to the base media store path. This is mainly used when we want
+    to write to the backup media store (when one is configured)
+    """
 
-    def default_thumbnail(self, default_top_level, default_sub_type, width,
-                          height, content_type, method):
+    def __init__(self, primary_base_path):
+        self.base_path = primary_base_path
+
+    def default_thumbnail_rel(self, default_top_level, default_sub_type, width,
+                              height, content_type, method):
         top_level_type, sub_type = content_type.split("/")
         file_name = "%i-%i-%s-%s-%s" % (
             width, height, top_level_type, sub_type, method
         )
         return os.path.join(
-            self.base_path, "default_thumbnails", default_top_level,
+            "default_thumbnails", default_top_level,
             default_sub_type, file_name
         )
 
-    def local_media_filepath(self, media_id):
+    default_thumbnail = _wrap_in_base_path(default_thumbnail_rel)
+
+    def local_media_filepath_rel(self, media_id):
         return os.path.join(
-            self.base_path, "local_content",
+            "local_content",
             media_id[0:2], media_id[2:4], media_id[4:]
         )
 
-    def local_media_thumbnail(self, media_id, width, height, content_type,
-                              method):
+    local_media_filepath = _wrap_in_base_path(local_media_filepath_rel)
+
+    def local_media_thumbnail_rel(self, media_id, width, height, content_type,
+                                  method):
         top_level_type, sub_type = content_type.split("/")
         file_name = "%i-%i-%s-%s-%s" % (
             width, height, top_level_type, sub_type, method
         )
         return os.path.join(
-            self.base_path, "local_thumbnails",
+            "local_thumbnails",
             media_id[0:2], media_id[2:4], media_id[4:],
             file_name
         )
 
-    def remote_media_filepath(self, server_name, file_id):
+    local_media_thumbnail = _wrap_in_base_path(local_media_thumbnail_rel)
+
+    def remote_media_filepath_rel(self, server_name, file_id):
         return os.path.join(
-            self.base_path, "remote_content", server_name,
+            "remote_content", server_name,
             file_id[0:2], file_id[2:4], file_id[4:]
         )
 
-    def remote_media_thumbnail(self, server_name, file_id, width, height,
-                               content_type, method):
+    remote_media_filepath = _wrap_in_base_path(remote_media_filepath_rel)
+
+    def remote_media_thumbnail_rel(self, server_name, file_id, width, height,
+                                   content_type, method):
         top_level_type, sub_type = content_type.split("/")
         file_name = "%i-%i-%s-%s" % (width, height, top_level_type, sub_type)
         return os.path.join(
-            self.base_path, "remote_thumbnail", server_name,
+            "remote_thumbnail", server_name,
             file_id[0:2], file_id[2:4], file_id[4:],
             file_name
         )
 
+    remote_media_thumbnail = _wrap_in_base_path(remote_media_thumbnail_rel)
+
     def remote_media_thumbnail_dir(self, server_name, file_id):
         return os.path.join(
             self.base_path, "remote_thumbnail", server_name,
             file_id[0:2], file_id[2:4], file_id[4:],
         )
 
-    def url_cache_filepath(self, media_id):
-        return os.path.join(
-            self.base_path, "url_cache",
-            media_id[0:2], media_id[2:4], media_id[4:]
-        )
+    def url_cache_filepath_rel(self, media_id):
+        if NEW_FORMAT_ID_RE.match(media_id):
+            # Media id is of the form <DATE><RANDOM_STRING>
+            # E.g.: 2017-09-28-fsdRDt24DS234dsf
+            return os.path.join(
+                "url_cache",
+                media_id[:10], media_id[11:]
+            )
+        else:
+            return os.path.join(
+                "url_cache",
+                media_id[0:2], media_id[2:4], media_id[4:],
+            )
+
+    url_cache_filepath = _wrap_in_base_path(url_cache_filepath_rel)
+
+    def url_cache_filepath_dirs_to_delete(self, media_id):
+        "The dirs to try and remove if we delete the media_id file"
+        if NEW_FORMAT_ID_RE.match(media_id):
+            return [
+                os.path.join(
+                    self.base_path, "url_cache",
+                    media_id[:10],
+                ),
+            ]
+        else:
+            return [
+                os.path.join(
+                    self.base_path, "url_cache",
+                    media_id[0:2], media_id[2:4],
+                ),
+                os.path.join(
+                    self.base_path, "url_cache",
+                    media_id[0:2],
+                ),
+            ]
+
+    def url_cache_thumbnail_rel(self, media_id, width, height, content_type,
+                                method):
+        # Media id is of the form <DATE><RANDOM_STRING>
+        # E.g.: 2017-09-28-fsdRDt24DS234dsf
 
-    def url_cache_thumbnail(self, media_id, width, height, content_type,
-                            method):
         top_level_type, sub_type = content_type.split("/")
         file_name = "%i-%i-%s-%s-%s" % (
             width, height, top_level_type, sub_type, method
         )
-        return os.path.join(
-            self.base_path, "url_cache_thumbnails",
-            media_id[0:2], media_id[2:4], media_id[4:],
-            file_name
-        )
+
+        if NEW_FORMAT_ID_RE.match(media_id):
+            return os.path.join(
+                "url_cache_thumbnails",
+                media_id[:10], media_id[11:],
+                file_name
+            )
+        else:
+            return os.path.join(
+                "url_cache_thumbnails",
+                media_id[0:2], media_id[2:4], media_id[4:],
+                file_name
+            )
+
+    url_cache_thumbnail = _wrap_in_base_path(url_cache_thumbnail_rel)
+
+    def url_cache_thumbnail_directory(self, media_id):
+        # Media id is of the form <DATE><RANDOM_STRING>
+        # E.g.: 2017-09-28-fsdRDt24DS234dsf
+
+        if NEW_FORMAT_ID_RE.match(media_id):
+            return os.path.join(
+                self.base_path, "url_cache_thumbnails",
+                media_id[:10], media_id[11:],
+            )
+        else:
+            return os.path.join(
+                self.base_path, "url_cache_thumbnails",
+                media_id[0:2], media_id[2:4], media_id[4:],
+            )
+
+    def url_cache_thumbnail_dirs_to_delete(self, media_id):
+        "The dirs to try and remove if we delete the media_id thumbnails"
+        # Media id is of the form <DATE><RANDOM_STRING>
+        # E.g.: 2017-09-28-fsdRDt24DS234dsf
+        if NEW_FORMAT_ID_RE.match(media_id):
+            return [
+                os.path.join(
+                    self.base_path, "url_cache_thumbnails",
+                    media_id[:10], media_id[11:],
+                ),
+                os.path.join(
+                    self.base_path, "url_cache_thumbnails",
+                    media_id[:10],
+                ),
+            ]
+        else:
+            return [
+                os.path.join(
+                    self.base_path, "url_cache_thumbnails",
+                    media_id[0:2], media_id[2:4], media_id[4:],
+                ),
+                os.path.join(
+                    self.base_path, "url_cache_thumbnails",
+                    media_id[0:2], media_id[2:4],
+                ),
+                os.path.join(
+                    self.base_path, "url_cache_thumbnails",
+                    media_id[0:2],
+                ),
+            ]
diff --git a/synapse/rest/media/v1/media_repository.py b/synapse/rest/media/v1/media_repository.py
index 0ea1248ce6..eed9056a2f 100644
--- a/synapse/rest/media/v1/media_repository.py
+++ b/synapse/rest/media/v1/media_repository.py
@@ -33,7 +33,7 @@ from synapse.api.errors import SynapseError, HttpResponseException, \
 
 from synapse.util.async import Linearizer
 from synapse.util.stringutils import is_ascii
-from synapse.util.logcontext import preserve_context_over_fn
+from synapse.util.logcontext import make_deferred_yieldable, preserve_fn
 from synapse.util.retryutils import NotRetryingDestination
 
 import os
@@ -59,7 +59,14 @@ class MediaRepository(object):
         self.store = hs.get_datastore()
         self.max_upload_size = hs.config.max_upload_size
         self.max_image_pixels = hs.config.max_image_pixels
-        self.filepaths = MediaFilePaths(hs.config.media_store_path)
+
+        self.primary_base_path = hs.config.media_store_path
+        self.filepaths = MediaFilePaths(self.primary_base_path)
+
+        self.backup_base_path = hs.config.backup_media_store_path
+
+        self.synchronous_backup_media_store = hs.config.synchronous_backup_media_store
+
         self.dynamic_thumbnails = hs.config.dynamic_thumbnails
         self.thumbnail_requirements = hs.config.thumbnail_requirements
 
@@ -87,18 +94,86 @@ class MediaRepository(object):
         if not os.path.exists(dirname):
             os.makedirs(dirname)
 
+    @staticmethod
+    def _write_file_synchronously(source, fname):
+        """Write `source` to the path `fname` synchronously. Should be called
+        from a thread.
+
+        Args:
+            source: A file like object to be written
+            fname (str): Path to write to
+        """
+        MediaRepository._makedirs(fname)
+        source.seek(0)  # Ensure we read from the start of the file
+        with open(fname, "wb") as f:
+            shutil.copyfileobj(source, f)
+
+    @defer.inlineCallbacks
+    def write_to_file_and_backup(self, source, path):
+        """Write `source` to the on disk media store, and also the backup store
+        if configured.
+
+        Args:
+            source: A file like object that should be written
+            path (str): Relative path to write file to
+
+        Returns:
+            Deferred[str]: the file path written to in the primary media store
+        """
+        fname = os.path.join(self.primary_base_path, path)
+
+        # Write to the main repository
+        yield make_deferred_yieldable(threads.deferToThread(
+            self._write_file_synchronously, source, fname,
+        ))
+
+        # Write to backup repository
+        yield self.copy_to_backup(path)
+
+        defer.returnValue(fname)
+
+    @defer.inlineCallbacks
+    def copy_to_backup(self, path):
+        """Copy a file from the primary to backup media store, if configured.
+
+        Args:
+            path(str): Relative path to write file to
+        """
+        if self.backup_base_path:
+            primary_fname = os.path.join(self.primary_base_path, path)
+            backup_fname = os.path.join(self.backup_base_path, path)
+
+            # We can either wait for successful writing to the backup repository
+            # or write in the background and immediately return
+            if self.synchronous_backup_media_store:
+                yield make_deferred_yieldable(threads.deferToThread(
+                    shutil.copyfile, primary_fname, backup_fname,
+                ))
+            else:
+                preserve_fn(threads.deferToThread)(
+                    shutil.copyfile, primary_fname, backup_fname,
+                )
+
     @defer.inlineCallbacks
     def create_content(self, media_type, upload_name, content, content_length,
                        auth_user):
+        """Store uploaded content for a local user and return the mxc URL
+
+        Args:
+            media_type(str): The content type of the file
+            upload_name(str): The name of the file
+            content: A file like object that is the content to store
+            content_length(int): The length of the content
+            auth_user(str): The user_id of the uploader
+
+        Returns:
+            Deferred[str]: The mxc url of the stored content
+        """
         media_id = random_string(24)
 
-        fname = self.filepaths.local_media_filepath(media_id)
-        self._makedirs(fname)
-
-        # This shouldn't block for very long because the content will have
-        # already been uploaded at this point.
-        with open(fname, "wb") as f:
-            f.write(content)
+        fname = yield self.write_to_file_and_backup(
+            content, self.filepaths.local_media_filepath_rel(media_id)
+        )
 
         logger.info("Stored local media in file %r", fname)
 
@@ -115,7 +190,7 @@ class MediaRepository(object):
             "media_length": content_length,
         }
 
-        yield self._generate_local_thumbnails(media_id, media_info)
+        yield self._generate_thumbnails(None, media_id, media_info)
 
         defer.returnValue("mxc://%s/%s" % (self.server_name, media_id))
 
@@ -148,9 +223,10 @@ class MediaRepository(object):
     def _download_remote_file(self, server_name, media_id):
         file_id = random_string(24)
 
-        fname = self.filepaths.remote_media_filepath(
+        fpath = self.filepaths.remote_media_filepath_rel(
             server_name, file_id
         )
+        fname = os.path.join(self.primary_base_path, fpath)
         self._makedirs(fname)
 
         try:
@@ -192,6 +268,8 @@ class MediaRepository(object):
                                      server_name, media_id)
                     raise SynapseError(502, "Failed to fetch remote media")
 
+            yield self.copy_to_backup(fpath)
+
             media_type = headers["Content-Type"][0]
             time_now_ms = self.clock.time_msec()
 
@@ -232,7 +310,7 @@ class MediaRepository(object):
                 media_length=length,
                 filesystem_id=file_id,
             )
-        except:
+        except Exception:
             os.remove(fname)
             raise
 
@@ -244,7 +322,7 @@ class MediaRepository(object):
             "filesystem_id": file_id,
         }
 
-        yield self._generate_remote_thumbnails(
+        yield self._generate_thumbnails(
             server_name, media_id, media_info
         )
 
@@ -253,9 +331,8 @@ class MediaRepository(object):
     def _get_thumbnail_requirements(self, media_type):
         return self.thumbnail_requirements.get(media_type, ())
 
-    def _generate_thumbnail(self, input_path, t_path, t_width, t_height,
+    def _generate_thumbnail(self, thumbnailer, t_width, t_height,
                             t_method, t_type):
-        thumbnailer = Thumbnailer(input_path)
         m_width = thumbnailer.width
         m_height = thumbnailer.height
 
@@ -267,72 +344,105 @@ class MediaRepository(object):
             return
 
         if t_method == "crop":
-            t_len = thumbnailer.crop(t_path, t_width, t_height, t_type)
+            t_byte_source = thumbnailer.crop(t_width, t_height, t_type)
         elif t_method == "scale":
             t_width, t_height = thumbnailer.aspect(t_width, t_height)
             t_width = min(m_width, t_width)
             t_height = min(m_height, t_height)
-            t_len = thumbnailer.scale(t_path, t_width, t_height, t_type)
+            t_byte_source = thumbnailer.scale(t_width, t_height, t_type)
         else:
-            t_len = None
+            t_byte_source = None
 
-        return t_len
+        return t_byte_source
 
     @defer.inlineCallbacks
     def generate_local_exact_thumbnail(self, media_id, t_width, t_height,
                                        t_method, t_type):
         input_path = self.filepaths.local_media_filepath(media_id)
 
-        t_path = self.filepaths.local_media_thumbnail(
-            media_id, t_width, t_height, t_type, t_method
-        )
-        self._makedirs(t_path)
-
-        t_len = yield preserve_context_over_fn(
-            threads.deferToThread,
+        thumbnailer = Thumbnailer(input_path)
+        t_byte_source = yield make_deferred_yieldable(threads.deferToThread(
             self._generate_thumbnail,
-            input_path, t_path, t_width, t_height, t_method, t_type
-        )
+            thumbnailer, t_width, t_height, t_method, t_type
+        ))
+
+        if t_byte_source:
+            try:
+                output_path = yield self.write_to_file_and_backup(
+                    t_byte_source,
+                    self.filepaths.local_media_thumbnail_rel(
+                        media_id, t_width, t_height, t_type, t_method
+                    )
+                )
+            finally:
+                t_byte_source.close()
+
+            logger.info("Stored thumbnail in file %r", output_path)
+
+            t_len = os.path.getsize(output_path)
 
-        if t_len:
             yield self.store.store_local_thumbnail(
                 media_id, t_width, t_height, t_type, t_method, t_len
             )
 
-            defer.returnValue(t_path)
+            defer.returnValue(output_path)
 
     @defer.inlineCallbacks
     def generate_remote_exact_thumbnail(self, server_name, file_id, media_id,
                                         t_width, t_height, t_method, t_type):
         input_path = self.filepaths.remote_media_filepath(server_name, file_id)
 
-        t_path = self.filepaths.remote_media_thumbnail(
-            server_name, file_id, t_width, t_height, t_type, t_method
-        )
-        self._makedirs(t_path)
-
-        t_len = yield preserve_context_over_fn(
-            threads.deferToThread,
+        thumbnailer = Thumbnailer(input_path)
+        t_byte_source = yield make_deferred_yieldable(threads.deferToThread(
             self._generate_thumbnail,
-            input_path, t_path, t_width, t_height, t_method, t_type
-        )
+            thumbnailer, t_width, t_height, t_method, t_type
+        ))
+
+        if t_byte_source:
+            try:
+                output_path = yield self.write_to_file_and_backup(
+                    t_byte_source,
+                    self.filepaths.remote_media_thumbnail_rel(
+                        server_name, file_id, t_width, t_height, t_type, t_method
+                    )
+                )
+            finally:
+                t_byte_source.close()
+
+            logger.info("Stored thumbnail in file %r", output_path)
+
+            t_len = os.path.getsize(output_path)
 
-        if t_len:
             yield self.store.store_remote_media_thumbnail(
                 server_name, media_id, file_id,
                 t_width, t_height, t_type, t_method, t_len
             )
 
-            defer.returnValue(t_path)
+            defer.returnValue(output_path)
 
     @defer.inlineCallbacks
-    def _generate_local_thumbnails(self, media_id, media_info, url_cache=False):
+    def _generate_thumbnails(self, server_name, media_id, media_info, url_cache=False):
+        """Generate and store thumbnails for an image.
+
+        Args:
+            server_name(str|None): The server name if remote media, else None if local
+            media_id(str)
+            media_info(dict)
+            url_cache(bool): If we are thumbnailing images downloaded for the URL cache,
+                used exclusively by the url previewer
+
+        Returns:
+            Deferred[dict]: Dict with "width" and "height" keys of original image
+        """
         media_type = media_info["media_type"]
+        file_id = media_info.get("filesystem_id")
         requirements = self._get_thumbnail_requirements(media_type)
         if not requirements:
             return
 
-        if url_cache:
+        if server_name:
+            input_path = self.filepaths.remote_media_filepath(server_name, file_id)
+        elif url_cache:
             input_path = self.filepaths.url_cache_filepath(media_id)
         else:
             input_path = self.filepaths.local_media_filepath(media_id)
@@ -348,135 +458,72 @@ class MediaRepository(object):
             )
             return
 
-        local_thumbnails = []
-
-        def generate_thumbnails():
-            scales = set()
-            crops = set()
-            for r_width, r_height, r_method, r_type in requirements:
-                if r_method == "scale":
-                    t_width, t_height = thumbnailer.aspect(r_width, r_height)
-                    scales.add((
-                        min(m_width, t_width), min(m_height, t_height), r_type,
-                    ))
-                elif r_method == "crop":
-                    crops.add((r_width, r_height, r_type))
-
-            for t_width, t_height, t_type in scales:
-                t_method = "scale"
-                if url_cache:
-                    t_path = self.filepaths.url_cache_thumbnail(
-                        media_id, t_width, t_height, t_type, t_method
-                    )
-                else:
-                    t_path = self.filepaths.local_media_thumbnail(
-                        media_id, t_width, t_height, t_type, t_method
-                    )
-                self._makedirs(t_path)
-                t_len = thumbnailer.scale(t_path, t_width, t_height, t_type)
+        # We deduplicate the thumbnail sizes by ignoring the cropped versions if
+        # they have the same dimensions of a scaled one.
+        thumbnails = {}
+        for r_width, r_height, r_method, r_type in requirements:
+            if r_method == "crop":
+                thumbnails.setdefault((r_width, r_height, r_type), r_method)
+            elif r_method == "scale":
+                t_width, t_height = thumbnailer.aspect(r_width, r_height)
+                t_width = min(m_width, t_width)
+                t_height = min(m_height, t_height)
+                thumbnails[(t_width, t_height, r_type)] = r_method
+
+        # Now we generate the thumbnails for each dimension, store it
+        for (t_width, t_height, t_type), t_method in thumbnails.iteritems():
+            # Work out the correct file name for thumbnail
+            if server_name:
+                file_path = self.filepaths.remote_media_thumbnail_rel(
+                    server_name, file_id, t_width, t_height, t_type, t_method
+                )
+            elif url_cache:
+                file_path = self.filepaths.url_cache_thumbnail_rel(
+                    media_id, t_width, t_height, t_type, t_method
+                )
+            else:
+                file_path = self.filepaths.local_media_thumbnail_rel(
+                    media_id, t_width, t_height, t_type, t_method
+                )
 
-                local_thumbnails.append((
-                    media_id, t_width, t_height, t_type, t_method, t_len
+            # Generate the thumbnail
+            if t_method == "crop":
+                t_byte_source = yield make_deferred_yieldable(threads.deferToThread(
+                    thumbnailer.crop,
+                    t_width, t_height, t_type,
                 ))
-
-            for t_width, t_height, t_type in crops:
-                if (t_width, t_height, t_type) in scales:
-                    # If the aspect ratio of the cropped thumbnail matches a purely
-                    # scaled one then there is no point in calculating a separate
-                    # thumbnail.
-                    continue
-                t_method = "crop"
-                if url_cache:
-                    t_path = self.filepaths.url_cache_thumbnail(
-                        media_id, t_width, t_height, t_type, t_method
-                    )
-                else:
-                    t_path = self.filepaths.local_media_thumbnail(
-                        media_id, t_width, t_height, t_type, t_method
-                    )
-                self._makedirs(t_path)
-                t_len = thumbnailer.crop(t_path, t_width, t_height, t_type)
-                local_thumbnails.append((
-                    media_id, t_width, t_height, t_type, t_method, t_len
+            elif t_method == "scale":
+                t_byte_source = yield make_deferred_yieldable(threads.deferToThread(
+                    thumbnailer.scale,
+                    t_width, t_height, t_type,
                 ))
+            else:
+                logger.error("Unrecognized method: %r", t_method)
+                continue
 
-        yield preserve_context_over_fn(threads.deferToThread, generate_thumbnails)
-
-        for l in local_thumbnails:
-            yield self.store.store_local_thumbnail(*l)
-
-        defer.returnValue({
-            "width": m_width,
-            "height": m_height,
-        })
-
-    @defer.inlineCallbacks
-    def _generate_remote_thumbnails(self, server_name, media_id, media_info):
-        media_type = media_info["media_type"]
-        file_id = media_info["filesystem_id"]
-        requirements = self._get_thumbnail_requirements(media_type)
-        if not requirements:
-            return
+            if not t_byte_source:
+                continue
 
-        remote_thumbnails = []
+            try:
+                # Write to disk
+                output_path = yield self.write_to_file_and_backup(
+                    t_byte_source, file_path,
+                )
+            finally:
+                t_byte_source.close()
 
-        input_path = self.filepaths.remote_media_filepath(server_name, file_id)
-        thumbnailer = Thumbnailer(input_path)
-        m_width = thumbnailer.width
-        m_height = thumbnailer.height
+            t_len = os.path.getsize(output_path)
 
-        def generate_thumbnails():
-            if m_width * m_height >= self.max_image_pixels:
-                logger.info(
-                    "Image too large to thumbnail %r x %r > %r",
-                    m_width, m_height, self.max_image_pixels
-                )
-                return
-
-            scales = set()
-            crops = set()
-            for r_width, r_height, r_method, r_type in requirements:
-                if r_method == "scale":
-                    t_width, t_height = thumbnailer.aspect(r_width, r_height)
-                    scales.add((
-                        min(m_width, t_width), min(m_height, t_height), r_type,
-                    ))
-                elif r_method == "crop":
-                    crops.add((r_width, r_height, r_type))
-
-            for t_width, t_height, t_type in scales:
-                t_method = "scale"
-                t_path = self.filepaths.remote_media_thumbnail(
-                    server_name, file_id, t_width, t_height, t_type, t_method
-                )
-                self._makedirs(t_path)
-                t_len = thumbnailer.scale(t_path, t_width, t_height, t_type)
-                remote_thumbnails.append([
+            # Write to database
+            if server_name:
+                yield self.store.store_remote_media_thumbnail(
                     server_name, media_id, file_id,
                     t_width, t_height, t_type, t_method, t_len
-                ])
-
-            for t_width, t_height, t_type in crops:
-                if (t_width, t_height, t_type) in scales:
-                    # If the aspect ratio of the cropped thumbnail matches a purely
-                    # scaled one then there is no point in calculating a separate
-                    # thumbnail.
-                    continue
-                t_method = "crop"
-                t_path = self.filepaths.remote_media_thumbnail(
-                    server_name, file_id, t_width, t_height, t_type, t_method
                 )
-                self._makedirs(t_path)
-                t_len = thumbnailer.crop(t_path, t_width, t_height, t_type)
-                remote_thumbnails.append([
-                    server_name, media_id, file_id,
-                    t_width, t_height, t_type, t_method, t_len
-                ])
-
-        yield preserve_context_over_fn(threads.deferToThread, generate_thumbnails)
-
-        for r in remote_thumbnails:
-            yield self.store.store_remote_media_thumbnail(*r)
+            else:
+                yield self.store.store_local_thumbnail(
+                    media_id, t_width, t_height, t_type, t_method, t_len
+                )
 
         defer.returnValue({
             "width": m_width,
@@ -497,6 +544,8 @@ class MediaRepository(object):
 
             logger.info("Deleting: %r", key)
 
+            # TODO: Should we delete from the backup store
+
             with (yield self.remote_media_linearizer.queue(key)):
                 full_path = self.filepaths.remote_media_filepath(origin, file_id)
                 try:
diff --git a/synapse/rest/media/v1/preview_url_resource.py b/synapse/rest/media/v1/preview_url_resource.py
index b81a336c5d..40d2e664eb 100644
--- a/synapse/rest/media/v1/preview_url_resource.py
+++ b/synapse/rest/media/v1/preview_url_resource.py
@@ -20,11 +20,13 @@ from twisted.web.resource import Resource
 from synapse.api.errors import (
     SynapseError, Codes,
 )
+from synapse.util.logcontext import preserve_fn, make_deferred_yieldable
 from synapse.util.stringutils import random_string
 from synapse.util.caches.expiringcache import ExpiringCache
 from synapse.http.client import SpiderHttpClient
 from synapse.http.server import (
-    request_handler, respond_with_json_bytes
+    request_handler, respond_with_json_bytes,
+    respond_with_json,
 )
 from synapse.util.async import ObservableDeferred
 from synapse.util.stringutils import is_ascii
@@ -36,6 +38,9 @@ import cgi
 import ujson as json
 import urlparse
 import itertools
+import datetime
+import errno
+import shutil
 
 import logging
 logger = logging.getLogger(__name__)
@@ -56,19 +61,26 @@ class PreviewUrlResource(Resource):
         self.store = hs.get_datastore()
         self.client = SpiderHttpClient(hs)
         self.media_repo = media_repo
+        self.primary_base_path = media_repo.primary_base_path
 
         self.url_preview_url_blacklist = hs.config.url_preview_url_blacklist
 
-        # simple memory cache mapping urls to OG metadata
-        self.cache = ExpiringCache(
+        # memory cache mapping urls to an ObservableDeferred returning
+        # JSON-encoded OG metadata
+        self._cache = ExpiringCache(
             cache_name="url_previews",
             clock=self.clock,
             # don't spider URLs more often than once an hour
             expiry_ms=60 * 60 * 1000,
         )
-        self.cache.start()
+        self._cache.start()
 
-        self.downloads = {}
+        self._cleaner_loop = self.clock.looping_call(
+            self._expire_url_cache_data, 10 * 1000
+        )
+
+    def render_OPTIONS(self, request):
+        return respond_with_json(request, 200, {}, send_cors=True)
 
     def render_GET(self, request):
         self._async_render_GET(request)
@@ -86,6 +98,7 @@ class PreviewUrlResource(Resource):
         else:
             ts = self.clock.time_msec()
 
+        # XXX: we could move this into _do_preview if we wanted.
         url_tuple = urlparse.urlsplit(url)
         for entry in self.url_preview_url_blacklist:
             match = True
@@ -118,53 +131,59 @@ class PreviewUrlResource(Resource):
                     Codes.UNKNOWN
                 )
 
-        # first check the memory cache - good to handle all the clients on this
-        # HS thundering away to preview the same URL at the same time.
-        og = self.cache.get(url)
-        if og:
-            respond_with_json_bytes(request, 200, json.dumps(og), send_cors=True)
-            return
+        # the in-memory cache:
+        # * ensures that only one request is active at a time
+        # * takes load off the DB for the thundering herds
+        # * also caches any failures (unlike the DB) so we don't keep
+        #    requesting the same endpoint
+
+        observable = self._cache.get(url)
+
+        if not observable:
+            download = preserve_fn(self._do_preview)(
+                url, requester.user, ts,
+            )
+            observable = ObservableDeferred(
+                download,
+                consumeErrors=True
+            )
+            self._cache[url] = observable
+        else:
+            logger.info("Returning cached response")
+
+        og = yield make_deferred_yieldable(observable.observe())
+        respond_with_json_bytes(request, 200, og, send_cors=True)
 
-        # then check the URL cache in the DB (which will also provide us with
+    @defer.inlineCallbacks
+    def _do_preview(self, url, user, ts):
+        """Check the db, and download the URL and build a preview
+
+        Args:
+            url (str):
+            user (str):
+            ts (int):
+
+        Returns:
+            Deferred[str]: json-encoded og data
+        """
+        # check the URL cache in the DB (which will also provide us with
         # historical previews, if we have any)
         cache_result = yield self.store.get_url_cache(url, ts)
         if (
             cache_result and
-            cache_result["download_ts"] + cache_result["expires"] > ts and
+            cache_result["expires_ts"] > ts and
             cache_result["response_code"] / 100 == 2
         ):
-            respond_with_json_bytes(
-                request, 200, cache_result["og"].encode('utf-8'),
-                send_cors=True
-            )
+            defer.returnValue(cache_result["og"])
             return
 
-        # Ensure only one download for a given URL is active at a time
-        download = self.downloads.get(url)
-        if download is None:
-            download = self._download_url(url, requester.user)
-            download = ObservableDeferred(
-                download,
-                consumeErrors=True
-            )
-            self.downloads[url] = download
-
-            @download.addBoth
-            def callback(media_info):
-                del self.downloads[url]
-                return media_info
-        media_info = yield download.observe()
-
-        # FIXME: we should probably update our cache now anyway, so that
-        # even if the OG calculation raises, we don't keep hammering on the
-        # remote server.  For now, leave it uncached to aid debugging OG
-        # calculation problems
+        media_info = yield self._download_url(url, user)
 
         logger.debug("got media_info of '%s'" % media_info)
 
         if _is_media(media_info['media_type']):
-            dims = yield self.media_repo._generate_local_thumbnails(
-                media_info['filesystem_id'], media_info, url_cache=True,
+            dims = yield self.media_repo._generate_thumbnails(
+                None, media_info['filesystem_id'], media_info, url_cache=True,
             )
 
             og = {
@@ -204,13 +223,13 @@ class PreviewUrlResource(Resource):
             # just rely on the caching on the master request to speed things up.
             if 'og:image' in og and og['og:image']:
                 image_info = yield self._download_url(
-                    _rebase_url(og['og:image'], media_info['uri']), requester.user
+                    _rebase_url(og['og:image'], media_info['uri']), user
                 )
 
                 if _is_media(image_info['media_type']):
                     # TODO: make sure we don't choke on white-on-transparent images
-                    dims = yield self.media_repo._generate_local_thumbnails(
-                        image_info['filesystem_id'], image_info, url_cache=True,
+                    dims = yield self.media_repo._generate_thumbnails(
+                        None, image_info['filesystem_id'], image_info, url_cache=True,
                     )
                     if dims:
                         og["og:image:width"] = dims['width']
@@ -231,21 +250,20 @@ class PreviewUrlResource(Resource):
 
         logger.debug("Calculated OG for %s as %s" % (url, og))
 
-        # store OG in ephemeral in-memory cache
-        self.cache[url] = og
+        jsonog = json.dumps(og)
 
         # store OG in history-aware DB cache
         yield self.store.store_url_cache(
             url,
             media_info["response_code"],
             media_info["etag"],
-            media_info["expires"],
-            json.dumps(og),
+            media_info["expires"] + media_info["created_ts"],
+            jsonog,
             media_info["filesystem_id"],
             media_info["created_ts"],
         )
 
-        respond_with_json_bytes(request, 200, json.dumps(og), send_cors=True)
+        defer.returnValue(jsonog)
 
     @defer.inlineCallbacks
     def _download_url(self, url, user):
@@ -253,10 +271,10 @@ class PreviewUrlResource(Resource):
         # we're most likely being explicitly triggered by a human rather than a
         # bot, so are we really a robot?
 
-        # XXX: horrible duplication with base_resource's _download_remote_file()
-        file_id = random_string(24)
+        file_id = datetime.date.today().isoformat() + '_' + random_string(16)
 
-        fname = self.filepaths.url_cache_filepath(file_id)
+        fpath = self.filepaths.url_cache_filepath_rel(file_id)
+        fname = os.path.join(self.primary_base_path, fpath)
         self.media_repo._makedirs(fname)
 
         try:
@@ -267,6 +285,8 @@ class PreviewUrlResource(Resource):
                 )
                 # FIXME: pass through 404s and other error messages nicely
 
+            yield self.media_repo.copy_to_backup(fpath)
+
             media_type = headers["Content-Type"][0]
             time_now_ms = self.clock.time_msec()
 
@@ -328,6 +348,95 @@ class PreviewUrlResource(Resource):
             "etag": headers["ETag"][0] if "ETag" in headers else None,
         })
 
+    @defer.inlineCallbacks
+    def _expire_url_cache_data(self):
+        """Clean up expired url cache content, media and thumbnails.
+        """
+        # TODO: Delete from backup media store
+
+        now = self.clock.time_msec()
+
+        logger.info("Running url preview cache expiry")
+
+        if not (yield self.store.has_completed_background_updates()):
+            logger.info("Still running DB updates; skipping expiry")
+            return
+
+        # First we delete expired url cache entries
+        media_ids = yield self.store.get_expired_url_cache(now)
+
+        removed_media = []
+        for media_id in media_ids:
+            fname = self.filepaths.url_cache_filepath(media_id)
+            try:
+                os.remove(fname)
+            except OSError as e:
+                # If the path doesn't exist, meh
+                if e.errno != errno.ENOENT:
+                    logger.warn("Failed to remove media: %r: %s", media_id, e)
+                    continue
+
+            removed_media.append(media_id)
+
+            try:
+                dirs = self.filepaths.url_cache_filepath_dirs_to_delete(media_id)
+                for dir in dirs:
+                    os.rmdir(dir)
+            except Exception:
+                pass
+
+        yield self.store.delete_url_cache(removed_media)
+
+        if removed_media:
+            logger.info("Deleted %d entries from url cache", len(removed_media))
+
+        # Now we delete old images associated with the url cache.
+        # These may be cached for a bit on the client (i.e., they
+        # may have a room open with a preview url thing open).
+        # So we wait a couple of days before deleting, just in case.
+        expire_before = now - 2 * 24 * 60 * 60 * 1000
+        media_ids = yield self.store.get_url_cache_media_before(expire_before)
+
+        removed_media = []
+        for media_id in media_ids:
+            fname = self.filepaths.url_cache_filepath(media_id)
+            try:
+                os.remove(fname)
+            except OSError as e:
+                # If the path doesn't exist, meh
+                if e.errno != errno.ENOENT:
+                    logger.warn("Failed to remove media: %r: %s", media_id, e)
+                    continue
+
+            try:
+                dirs = self.filepaths.url_cache_filepath_dirs_to_delete(media_id)
+                for dir in dirs:
+                    os.rmdir(dir)
+            except Exception:
+                pass
+
+            thumbnail_dir = self.filepaths.url_cache_thumbnail_directory(media_id)
+            try:
+                shutil.rmtree(thumbnail_dir)
+            except OSError as e:
+                # If the path doesn't exist, meh
+                if e.errno != errno.ENOENT:
+                    logger.warn("Failed to remove media: %r: %s", media_id, e)
+                    continue
+
+            removed_media.append(media_id)
+
+            try:
+                dirs = self.filepaths.url_cache_thumbnail_dirs_to_delete(media_id)
+                for dir in dirs:
+                    os.rmdir(dir)
+            except Exception:
+                pass
+
+        yield self.store.delete_url_cache_media(removed_media)
+
+        logger.info("Deleted %d media from url cache", len(removed_media))
+
 
 def decode_and_calc_og(body, media_uri, request_encoding=None):
     from lxml import etree
@@ -425,7 +534,14 @@ def _calc_og(tree, media_uri):
             from lxml import etree
 
             TAGS_TO_REMOVE = (
-                "header", "nav", "aside", "footer", "script", "style", etree.Comment
+                "header",
+                "nav",
+                "aside",
+                "footer",
+                "script",
+                "noscript",
+                "style",
+                etree.Comment
             )
 
             # Split all the text nodes into paragraphs (by splitting on new
diff --git a/synapse/rest/media/v1/thumbnailer.py b/synapse/rest/media/v1/thumbnailer.py
index 3868d4f65f..e1ee535b9a 100644
--- a/synapse/rest/media/v1/thumbnailer.py
+++ b/synapse/rest/media/v1/thumbnailer.py
@@ -50,12 +50,16 @@ class Thumbnailer(object):
         else:
             return ((max_height * self.width) // self.height, max_height)
 
-    def scale(self, output_path, width, height, output_type):
-        """Rescales the image to the given dimensions"""
+    def scale(self, width, height, output_type):
+        """Rescales the image to the given dimensions.
+
+        Returns:
+            BytesIO: the bytes of the encoded image ready to be written to disk
+        """
         scaled = self.image.resize((width, height), Image.ANTIALIAS)
-        return self.save_image(scaled, output_type, output_path)
+        return self._encode_image(scaled, output_type)
 
-    def crop(self, output_path, width, height, output_type):
+    def crop(self, width, height, output_type):
         """Rescales and crops the image to the given dimensions preserving
         aspect::
             (w_in / h_in) = (w_scaled / h_scaled)
@@ -65,6 +69,9 @@ class Thumbnailer(object):
         Args:
             max_width: The largest possible width.
             max_height: The larget possible height.
+
+        Returns:
+            BytesIO: the bytes of the encoded image ready to be written to disk
         """
         if width * self.height > height * self.width:
             scaled_height = (width * self.height) // self.width
@@ -82,13 +89,9 @@ class Thumbnailer(object):
             crop_left = (scaled_width - width) // 2
             crop_right = width + crop_left
             cropped = scaled_image.crop((crop_left, 0, crop_right, height))
-        return self.save_image(cropped, output_type, output_path)
+        return self._encode_image(cropped, output_type)
 
-    def save_image(self, output_image, output_type, output_path):
+    def _encode_image(self, output_image, output_type):
         output_bytes_io = BytesIO()
         output_image.save(output_bytes_io, self.FORMATS[output_type], quality=80)
-        output_bytes = output_bytes_io.getvalue()
-        with open(output_path, "wb") as output_file:
-            output_file.write(output_bytes)
-        logger.info("Stored thumbnail in file %r", output_path)
-        return len(output_bytes)
+        return output_bytes_io
diff --git a/synapse/rest/media/v1/upload_resource.py b/synapse/rest/media/v1/upload_resource.py
index 4ab33f73bf..f6f498cdc5 100644
--- a/synapse/rest/media/v1/upload_resource.py
+++ b/synapse/rest/media/v1/upload_resource.py
@@ -93,7 +93,7 @@ class UploadResource(Resource):
         # TODO(markjh): parse content-dispostion
 
         content_uri = yield self.media_repo.create_content(
-            media_type, upload_name, request.content.read(),
+            media_type, upload_name, request.content,
             content_length, requester.user
         )
 
diff --git a/synapse/server.py b/synapse/server.py
index 4d44af745e..99693071b6 100644
--- a/synapse/server.py
+++ b/synapse/server.py
@@ -39,24 +39,33 @@ from synapse.federation.transaction_queue import TransactionQueue
 from synapse.handlers import Handlers
 from synapse.handlers.appservice import ApplicationServicesHandler
 from synapse.handlers.auth import AuthHandler, MacaroonGeneartor
+from synapse.handlers.deactivate_account import DeactivateAccountHandler
 from synapse.handlers.devicemessage import DeviceMessageHandler
 from synapse.handlers.device import DeviceHandler
 from synapse.handlers.e2e_keys import E2eKeysHandler
 from synapse.handlers.presence import PresenceHandler
 from synapse.handlers.room_list import RoomListHandler
+from synapse.handlers.set_password import SetPasswordHandler
 from synapse.handlers.sync import SyncHandler
 from synapse.handlers.typing import TypingHandler
 from synapse.handlers.events import EventHandler, EventStreamHandler
 from synapse.handlers.initial_sync import InitialSyncHandler
 from synapse.handlers.receipts import ReceiptsHandler
 from synapse.handlers.read_marker import ReadMarkerHandler
-from synapse.handlers.user_directory import UserDirectoyHandler
+from synapse.handlers.user_directory import UserDirectoryHandler
+from synapse.handlers.groups_local import GroupsLocalHandler
+from synapse.handlers.profile import ProfileHandler
+from synapse.groups.groups_server import GroupsServerHandler
+from synapse.groups.attestations import GroupAttestionRenewer, GroupAttestationSigning
 from synapse.http.client import SimpleHttpClient, InsecureInterceptableContextFactory
 from synapse.http.matrixfederationclient import MatrixFederationHttpClient
 from synapse.notifier import Notifier
 from synapse.push.action_generator import ActionGenerator
 from synapse.push.pusherpool import PusherPool
-from synapse.rest.media.v1.media_repository import MediaRepository
+from synapse.rest.media.v1.media_repository import (
+    MediaRepository,
+    MediaRepositoryResource,
+)
 from synapse.state import StateHandler
 from synapse.storage import DataStore
 from synapse.streams.events import EventSources
@@ -86,17 +95,12 @@ class HomeServer(object):
     """
 
     DEPENDENCIES = [
-        'config',
-        'clock',
         'http_client',
         'db_pool',
-        'persistence_service',
         'replication_layer',
-        'datastore',
         'handlers',
         'v1auth',
         'auth',
-        'rest_servlet_factory',
         'state_handler',
         'presence_handler',
         'sync_handler',
@@ -112,19 +116,11 @@ class HomeServer(object):
         'application_service_scheduler',
         'application_service_handler',
         'device_message_handler',
+        'profile_handler',
+        'deactivate_account_handler',
+        'set_password_handler',
         'notifier',
-        'distributor',
-        'client_resource',
-        'resource_for_federation',
-        'resource_for_static_content',
-        'resource_for_web_client',
-        'resource_for_content_repo',
-        'resource_for_server_key',
-        'resource_for_server_key_v2',
-        'resource_for_media_repository',
-        'resource_for_metrics',
         'event_sources',
-        'ratelimiter',
         'keyring',
         'pusherpool',
         'event_builder_factory',
@@ -132,6 +128,7 @@ class HomeServer(object):
         'http_client_context_factory',
         'simple_http_client',
         'media_repository',
+        'media_repository_resource',
         'federation_transport_client',
         'federation_sender',
         'receipts_handler',
@@ -140,6 +137,10 @@ class HomeServer(object):
         'read_marker_handler',
         'action_generator',
         'user_directory_handler',
+        'groups_local_handler',
+        'groups_server_handler',
+        'groups_attestation_signing',
+        'groups_attestation_renewer',
         'spam_checker',
     ]
 
@@ -174,6 +175,21 @@ class HomeServer(object):
     def is_mine_id(self, string):
         return string.split(":", 1)[1] == self.hostname
 
+    def get_clock(self):
+        return self.clock
+
+    def get_datastore(self):
+        return self.datastore
+
+    def get_config(self):
+        return self.config
+
+    def get_distributor(self):
+        return self.distributor
+
+    def get_ratelimiter(self):
+        return self.ratelimiter
+
     def build_replication_layer(self):
         return initialize_http_replication(self)
 
@@ -253,6 +269,15 @@ class HomeServer(object):
     def build_initial_sync_handler(self):
         return InitialSyncHandler(self)
 
+    def build_profile_handler(self):
+        return ProfileHandler(self)
+
+    def build_deactivate_account_handler(self):
+        return DeactivateAccountHandler(self)
+
+    def build_set_password_handler(self):
+        return SetPasswordHandler(self)
+
     def build_event_sources(self):
         return EventSources(self)
 
@@ -282,6 +307,11 @@ class HomeServer(object):
             **self.db_config.get("args", {})
         )
 
+    def build_media_repository_resource(self):
+        # build the media repo resource. This indirects through the HomeServer
+        # to ensure that we only have a single instance of
+        return MediaRepositoryResource(self)
+
     def build_media_repository(self):
         return MediaRepository(self)
 
@@ -309,7 +339,19 @@ class HomeServer(object):
         return ActionGenerator(self)
 
     def build_user_directory_handler(self):
-        return UserDirectoyHandler(self)
+        return UserDirectoryHandler(self)
+
+    def build_groups_local_handler(self):
+        return GroupsLocalHandler(self)
+
+    def build_groups_server_handler(self):
+        return GroupsServerHandler(self)
+
+    def build_groups_attestation_signing(self):
+        return GroupAttestationSigning(self)
+
+    def build_groups_attestation_renewer(self):
+        return GroupAttestionRenewer(self)
 
     def build_spam_checker(self):
         return SpamChecker(self)
diff --git a/synapse/server.pyi b/synapse/server.pyi
index 9570df5537..41416ef252 100644
--- a/synapse/server.pyi
+++ b/synapse/server.pyi
@@ -1,10 +1,16 @@
 import synapse.api.auth
+import synapse.federation.transaction_queue
+import synapse.federation.transport.client
 import synapse.handlers
 import synapse.handlers.auth
+import synapse.handlers.deactivate_account
 import synapse.handlers.device
 import synapse.handlers.e2e_keys
-import synapse.storage
+import synapse.handlers.set_password
+import synapse.rest.media.v1.media_repository
 import synapse.state
+import synapse.storage
+
 
 class HomeServer(object):
     def get_auth(self) -> synapse.api.auth.Auth:
@@ -27,3 +33,21 @@ class HomeServer(object):
 
     def get_state_handler(self) -> synapse.state.StateHandler:
         pass
+
+    def get_deactivate_account_handler(self) -> synapse.handlers.deactivate_account.DeactivateAccountHandler:
+        pass
+
+    def get_set_password_handler(self) -> synapse.handlers.set_password.SetPasswordHandler:
+        pass
+
+    def get_federation_sender(self) -> synapse.federation.transaction_queue.TransactionQueue:
+        pass
+
+    def get_federation_transport_client(self) -> synapse.federation.transport.client.TransportLayerClient:
+        pass
+
+    def get_media_repository_resource(self) -> synapse.rest.media.v1.media_repository.MediaRepositoryResource:
+        pass
+
+    def get_media_repository(self) -> synapse.rest.media.v1.media_repository.MediaRepository:
+        pass
diff --git a/synapse/state.py b/synapse/state.py
index 390799fbd5..9e624b4937 100644
--- a/synapse/state.py
+++ b/synapse/state.py
@@ -288,6 +288,9 @@ class StateHandler(object):
         """
         logger.debug("resolve_state_groups event_ids %s", event_ids)
 
+        # map from state group id to the state in that state group (where
+        # 'state' is a map from state key to event id)
+        # dict[int, dict[(str, str), str]]
         state_groups_ids = yield self.store.get_state_groups_ids(
             room_id, event_ids
         )
@@ -320,11 +323,15 @@ class StateHandler(object):
                 "Resolving state for %s with %d groups", room_id, len(state_groups_ids)
             )
 
+            # build a map from state key to the event_ids which set that state.
+            # dict[(str, str), set[str])
             state = {}
             for st in state_groups_ids.values():
                 for key, e_id in st.items():
                     state.setdefault(key, set()).add(e_id)
 
+            # build a map from state key to the event_ids which set that state,
+            # including only those where there are state keys in conflict.
             conflicted_state = {
                 k: list(v)
                 for k, v in state.items()
@@ -494,8 +501,14 @@ def _resolve_with_state_fac(unconflicted_state, conflicted_state,
 
     logger.info("Asking for %d conflicted events", len(needed_events))
 
+    # dict[str, FrozenEvent]: a map from state event id to event. Only includes
+    # the state events which are in conflict.
     state_map = yield state_map_factory(needed_events)
 
+    # get the ids of the auth events which allow us to authenticate the
+    # conflicted state, picking only from the unconflicting state.
+    #
+    # dict[(str, str), str]: a map from state key to event id
     auth_events = _create_auth_events_from_maps(
         unconflicted_state, conflicted_state, state_map
     )
@@ -547,7 +560,7 @@ def _resolve_with_state(unconflicted_state_ids, conflicted_state_ds, auth_event_
         resolved_state = _resolve_state_events(
             conflicted_state, auth_events
         )
-    except:
+    except Exception:
         logger.exception("Failed to resolve state")
         raise
 
diff --git a/synapse/storage/__init__.py b/synapse/storage/__init__.py
index b92472df33..d01d46338a 100644
--- a/synapse/storage/__init__.py
+++ b/synapse/storage/__init__.py
@@ -37,7 +37,7 @@ from .media_repository import MediaRepositoryStore
 from .rejections import RejectionsStore
 from .event_push_actions import EventPushActionsStore
 from .deviceinbox import DeviceInboxStore
-
+from .group_server import GroupServerStore
 from .state import StateStore
 from .signatures import SignatureStore
 from .filtering import FilteringStore
@@ -88,6 +88,7 @@ class DataStore(RoomMemberStore, RoomStore,
                 DeviceStore,
                 DeviceInboxStore,
                 UserDirectoryStore,
+                GroupServerStore,
                 ):
 
     def __init__(self, db_conn, hs):
@@ -135,6 +136,9 @@ class DataStore(RoomMemberStore, RoomStore,
             db_conn, "pushers", "id",
             extra_tables=[("deleted_pushers", "stream_id")],
         )
+        self._group_updates_id_gen = StreamIdGenerator(
+            db_conn, "local_group_updates", "stream_id",
+        )
 
         if isinstance(self.database_engine, PostgresEngine):
             self._cache_id_gen = StreamIdGenerator(
@@ -235,6 +239,18 @@ class DataStore(RoomMemberStore, RoomStore,
             prefilled_cache=curr_state_delta_prefill,
         )
 
+        _group_updates_prefill, min_group_updates_id = self._get_cache_dict(
+            db_conn, "local_group_updates",
+            entity_column="user_id",
+            stream_column="stream_id",
+            max_value=self._group_updates_id_gen.get_current_token(),
+            limit=1000,
+        )
+        self._group_updates_stream_cache = StreamChangeCache(
+            "_group_updates_stream_cache", min_group_updates_id,
+            prefilled_cache=_group_updates_prefill,
+        )
+
         cur = LoggingTransaction(
             db_conn.cursor(),
             name="_find_stream_orderings_for_times_txn",
@@ -252,7 +268,7 @@ class DataStore(RoomMemberStore, RoomStore,
         self._stream_order_on_start = self.get_room_max_stream_ordering()
         self._min_stream_order_on_start = self.get_room_min_stream_ordering()
 
-        super(DataStore, self).__init__(hs)
+        super(DataStore, self).__init__(db_conn, hs)
 
     def take_presence_startup_info(self):
         active_on_startup = self._presence_on_startup
diff --git a/synapse/storage/_base.py b/synapse/storage/_base.py
index 6f54036d67..b971f0cb18 100644
--- a/synapse/storage/_base.py
+++ b/synapse/storage/_base.py
@@ -16,8 +16,6 @@ import logging
 
 from synapse.api.errors import StoreError
 from synapse.util.logcontext import LoggingContext, PreserveLoggingContext
-from synapse.util.caches import CACHE_SIZE_FACTOR
-from synapse.util.caches.dictionary_cache import DictionaryCache
 from synapse.util.caches.descriptors import Cache
 from synapse.storage.engines import PostgresEngine
 import synapse.metrics
@@ -103,7 +101,7 @@ class LoggingTransaction(object):
                     "[SQL values] {%s} %r",
                     self.name, args[0]
                 )
-            except:
+            except Exception:
                 # Don't let logging failures stop SQL from working
                 pass
 
@@ -162,7 +160,7 @@ class PerformanceCounters(object):
 class SQLBaseStore(object):
     _TXN_ID = 0
 
-    def __init__(self, hs):
+    def __init__(self, db_conn, hs):
         self.hs = hs
         self._clock = hs.get_clock()
         self._db_pool = hs.get_db_pool()
@@ -180,10 +178,6 @@ class SQLBaseStore(object):
         self._get_event_cache = Cache("*getEvent*", keylen=3,
                                       max_entries=hs.config.event_cache_size)
 
-        self._state_group_cache = DictionaryCache(
-            "*stateGroupCache*", 100000 * CACHE_SIZE_FACTOR
-        )
-
         self._event_fetch_lock = threading.Condition()
         self._event_fetch_list = []
         self._event_fetch_ongoing = 0
@@ -475,23 +469,53 @@ class SQLBaseStore(object):
 
         txn.executemany(sql, vals)
 
+    @defer.inlineCallbacks
     def _simple_upsert(self, table, keyvalues, values,
                        insertion_values={}, desc="_simple_upsert", lock=True):
         """
+
+        `lock` should generally be set to True (the default), but can be set
+        to False if either of the following are true:
+
+        * there is a UNIQUE INDEX on the key columns. In this case a conflict
+          will cause an IntegrityError in which case this function will retry
+          the update.
+
+        * we somehow know that we are the only thread which will be updating
+          this table.
+
         Args:
             table (str): The table to upsert into
             keyvalues (dict): The unique key tables and their new values
             values (dict): The nonunique columns and their new values
-            insertion_values (dict): key/values to use when inserting
+            insertion_values (dict): additional key/values to use only when
+                inserting
+            lock (bool): True to lock the table when doing the upsert.
         Returns:
             Deferred(bool): True if a new entry was created, False if an
                 existing one was updated.
         """
-        return self.runInteraction(
-            desc,
-            self._simple_upsert_txn, table, keyvalues, values, insertion_values,
-            lock
-        )
+        attempts = 0
+        while True:
+            try:
+                result = yield self.runInteraction(
+                    desc,
+                    self._simple_upsert_txn, table, keyvalues, values, insertion_values,
+                    lock=lock
+                )
+                defer.returnValue(result)
+            except self.database_engine.module.IntegrityError as e:
+                attempts += 1
+                if attempts >= 5:
+                    # don't retry forever, because things other than races
+                    # can cause IntegrityErrors
+                    raise
+
+                # presumably we raced with another transaction: let's retry.
+                logger.warn(
+                    "IntegrityError when upserting into %s; retrying: %s",
+                    table, e
+                )
 
     def _simple_upsert_txn(self, txn, table, keyvalues, values, insertion_values={},
                            lock=True):
@@ -499,7 +523,7 @@ class SQLBaseStore(object):
         if lock:
             self.database_engine.lock_table(txn, table)
 
-        # Try to update
+        # First try to update.
         sql = "UPDATE %s SET %s WHERE %s" % (
             table,
             ", ".join("%s = ?" % (k,) for k in values),
@@ -508,28 +532,29 @@ class SQLBaseStore(object):
         sqlargs = values.values() + keyvalues.values()
 
         txn.execute(sql, sqlargs)
-        if txn.rowcount == 0:
-            # We didn't update and rows so insert a new one
-            allvalues = {}
-            allvalues.update(keyvalues)
-            allvalues.update(values)
-            allvalues.update(insertion_values)
+        if txn.rowcount > 0:
+            # successfully updated at least one row.
+            return False
 
-            sql = "INSERT INTO %s (%s) VALUES (%s)" % (
-                table,
-                ", ".join(k for k in allvalues),
-                ", ".join("?" for _ in allvalues)
-            )
-            txn.execute(sql, allvalues.values())
+        # We didn't update any rows so insert a new one
+        allvalues = {}
+        allvalues.update(keyvalues)
+        allvalues.update(values)
+        allvalues.update(insertion_values)
 
-            return True
-        else:
-            return False
+        sql = "INSERT INTO %s (%s) VALUES (%s)" % (
+            table,
+            ", ".join(k for k in allvalues),
+            ", ".join("?" for _ in allvalues)
+        )
+        txn.execute(sql, allvalues.values())
+        # successfully inserted
+        return True
 
     def _simple_select_one(self, table, keyvalues, retcols,
                            allow_none=False, desc="_simple_select_one"):
         """Executes a SELECT query on the named table, which is expected to
-        return a single row, returning a single column from it.
+        return a single row, returning multiple columns from it.
 
         Args:
             table : string giving the table name
@@ -582,20 +607,18 @@ class SQLBaseStore(object):
 
     @staticmethod
     def _simple_select_onecol_txn(txn, table, keyvalues, retcol):
-        if keyvalues:
-            where = "WHERE %s" % " AND ".join("%s = ?" % k for k in keyvalues.iterkeys())
-        else:
-            where = ""
-
         sql = (
-            "SELECT %(retcol)s FROM %(table)s %(where)s"
+            "SELECT %(retcol)s FROM %(table)s"
         ) % {
             "retcol": retcol,
             "table": table,
-            "where": where,
         }
 
-        txn.execute(sql, keyvalues.values())
+        if keyvalues:
+            sql += " WHERE %s" % " AND ".join("%s = ?" % k for k in keyvalues.iterkeys())
+            txn.execute(sql, keyvalues.values())
+        else:
+            txn.execute(sql)
 
         return [r[0] for r in txn]
 
@@ -606,7 +629,7 @@ class SQLBaseStore(object):
 
         Args:
             table (str): table name
-            keyvalues (dict): column names and values to select the rows with
+            keyvalues (dict|None): column names and values to select the rows with
             retcol (str): column whos value we wish to retrieve.
 
         Returns:
@@ -743,6 +766,33 @@ class SQLBaseStore(object):
         txn.execute(sql, values)
         return cls.cursor_to_dict(txn)
 
+    def _simple_update(self, table, keyvalues, updatevalues, desc):
+        return self.runInteraction(
+            desc,
+            self._simple_update_txn,
+            table, keyvalues, updatevalues,
+        )
+
+    @staticmethod
+    def _simple_update_txn(txn, table, keyvalues, updatevalues):
+        if keyvalues:
+            where = "WHERE %s" % " AND ".join("%s = ?" % k for k in keyvalues.iterkeys())
+        else:
+            where = ""
+
+        update_sql = "UPDATE %s SET %s %s" % (
+            table,
+            ", ".join("%s = ?" % (k,) for k in updatevalues),
+            where,
+        )
+
+        txn.execute(
+            update_sql,
+            updatevalues.values() + keyvalues.values()
+        )
+
+        return txn.rowcount
+
     def _simple_update_one(self, table, keyvalues, updatevalues,
                            desc="_simple_update_one"):
         """Executes an UPDATE query on the named table, setting new values for
@@ -768,27 +818,13 @@ class SQLBaseStore(object):
             table, keyvalues, updatevalues,
         )
 
-    @staticmethod
-    def _simple_update_one_txn(txn, table, keyvalues, updatevalues):
-        if keyvalues:
-            where = "WHERE %s" % " AND ".join("%s = ?" % k for k in keyvalues.iterkeys())
-        else:
-            where = ""
-
-        update_sql = "UPDATE %s SET %s %s" % (
-            table,
-            ", ".join("%s = ?" % (k,) for k in updatevalues),
-            where,
-        )
-
-        txn.execute(
-            update_sql,
-            updatevalues.values() + keyvalues.values()
-        )
+    @classmethod
+    def _simple_update_one_txn(cls, txn, table, keyvalues, updatevalues):
+        rowcount = cls._simple_update_txn(txn, table, keyvalues, updatevalues)
 
-        if txn.rowcount == 0:
+        if rowcount == 0:
             raise StoreError(404, "No row found")
-        if txn.rowcount > 1:
+        if rowcount > 1:
             raise StoreError(500, "More than one row matched")
 
     @staticmethod
diff --git a/synapse/storage/account_data.py b/synapse/storage/account_data.py
index ff14e54c11..56a0bde549 100644
--- a/synapse/storage/account_data.py
+++ b/synapse/storage/account_data.py
@@ -63,7 +63,7 @@ class AccountDataStore(SQLBaseStore):
             "get_account_data_for_user", get_account_data_for_user_txn
         )
 
-    @cachedInlineCallbacks(num_args=2)
+    @cachedInlineCallbacks(num_args=2, max_entries=5000)
     def get_global_account_data_by_type_for_user(self, data_type, user_id):
         """
         Returns:
@@ -222,9 +222,12 @@ class AccountDataStore(SQLBaseStore):
         """
         content_json = json.dumps(content)
 
-        def add_account_data_txn(txn, next_id):
-            self._simple_upsert_txn(
-                txn,
+        with self._account_data_id_gen.get_next() as next_id:
+            # no need to lock here as room_account_data has a unique constraint
+            # on (user_id, room_id, account_data_type) so _simple_upsert will
+            # retry if there is a conflict.
+            yield self._simple_upsert(
+                desc="add_room_account_data",
                 table="room_account_data",
                 keyvalues={
                     "user_id": user_id,
@@ -234,19 +237,20 @@ class AccountDataStore(SQLBaseStore):
                 values={
                     "stream_id": next_id,
                     "content": content_json,
-                }
-            )
-            txn.call_after(
-                self._account_data_stream_cache.entity_has_changed,
-                user_id, next_id,
+                },
+                lock=False,
             )
-            txn.call_after(self.get_account_data_for_user.invalidate, (user_id,))
-            self._update_max_stream_id(txn, next_id)
 
-        with self._account_data_id_gen.get_next() as next_id:
-            yield self.runInteraction(
-                "add_room_account_data", add_account_data_txn, next_id
-            )
+            # it's theoretically possible for the above to succeed and the
+            # below to fail - in which case we might reuse a stream id on
+            # restart, and the above update might not get propagated. That
+            # doesn't sound any worse than the whole update getting lost,
+            # which is what would happen if we combined the two into one
+            # transaction.
+            yield self._update_max_stream_id(next_id)
+
+            self._account_data_stream_cache.entity_has_changed(user_id, next_id)
+            self.get_account_data_for_user.invalidate((user_id,))
 
         result = self._account_data_id_gen.get_current_token()
         defer.returnValue(result)
@@ -263,9 +267,12 @@ class AccountDataStore(SQLBaseStore):
         """
         content_json = json.dumps(content)
 
-        def add_account_data_txn(txn, next_id):
-            self._simple_upsert_txn(
-                txn,
+        with self._account_data_id_gen.get_next() as next_id:
+            # no need to lock here as account_data has a unique constraint on
+            # (user_id, account_data_type) so _simple_upsert will retry if
+            # there is a conflict.
+            yield self._simple_upsert(
+                desc="add_user_account_data",
                 table="account_data",
                 keyvalues={
                     "user_id": user_id,
@@ -274,40 +281,46 @@ class AccountDataStore(SQLBaseStore):
                 values={
                     "stream_id": next_id,
                     "content": content_json,
-                }
+                },
+                lock=False,
             )
-            txn.call_after(
-                self._account_data_stream_cache.entity_has_changed,
+
+            # it's theoretically possible for the above to succeed and the
+            # below to fail - in which case we might reuse a stream id on
+            # restart, and the above update might not get propagated. That
+            # doesn't sound any worse than the whole update getting lost,
+            # which is what would happen if we combined the two into one
+            # transaction.
+            yield self._update_max_stream_id(next_id)
+
+            self._account_data_stream_cache.entity_has_changed(
                 user_id, next_id,
             )
-            txn.call_after(self.get_account_data_for_user.invalidate, (user_id,))
-            txn.call_after(
-                self.get_global_account_data_by_type_for_user.invalidate,
+            self.get_account_data_for_user.invalidate((user_id,))
+            self.get_global_account_data_by_type_for_user.invalidate(
                 (account_data_type, user_id,)
             )
-            self._update_max_stream_id(txn, next_id)
-
-        with self._account_data_id_gen.get_next() as next_id:
-            yield self.runInteraction(
-                "add_user_account_data", add_account_data_txn, next_id
-            )
 
         result = self._account_data_id_gen.get_current_token()
         defer.returnValue(result)
 
-    def _update_max_stream_id(self, txn, next_id):
+    def _update_max_stream_id(self, next_id):
         """Update the max stream_id
 
         Args:
-            txn: The database cursor
             next_id(int): The the revision to advance to.
         """
-        update_max_id_sql = (
-            "UPDATE account_data_max_stream_id"
-            " SET stream_id = ?"
-            " WHERE stream_id < ?"
+        def _update(txn):
+            update_max_id_sql = (
+                "UPDATE account_data_max_stream_id"
+                " SET stream_id = ?"
+                " WHERE stream_id < ?"
+            )
+            txn.execute(update_max_id_sql, (next_id, next_id))
+        return self.runInteraction(
+            "update_account_data_max_stream_id",
+            _update,
         )
-        txn.execute(update_max_id_sql, (next_id, next_id))
 
     @cachedInlineCallbacks(num_args=2, cache_context=True, max_entries=5000)
     def is_ignored_by(self, ignored_user_id, ignorer_user_id, cache_context):
diff --git a/synapse/storage/appservice.py b/synapse/storage/appservice.py
index c63935cb07..d8c84b7141 100644
--- a/synapse/storage/appservice.py
+++ b/synapse/storage/appservice.py
@@ -48,8 +48,8 @@ def _make_exclusive_regex(services_cache):
 
 class ApplicationServiceStore(SQLBaseStore):
 
-    def __init__(self, hs):
-        super(ApplicationServiceStore, self).__init__(hs)
+    def __init__(self, db_conn, hs):
+        super(ApplicationServiceStore, self).__init__(db_conn, hs)
         self.hostname = hs.hostname
         self.services_cache = load_appservices(
             hs.hostname,
@@ -173,8 +173,8 @@ class ApplicationServiceStore(SQLBaseStore):
 
 class ApplicationServiceTransactionStore(SQLBaseStore):
 
-    def __init__(self, hs):
-        super(ApplicationServiceTransactionStore, self).__init__(hs)
+    def __init__(self, db_conn, hs):
+        super(ApplicationServiceTransactionStore, self).__init__(db_conn, hs)
 
     @defer.inlineCallbacks
     def get_appservices_by_state(self, state):
diff --git a/synapse/storage/background_updates.py b/synapse/storage/background_updates.py
index 7157fb1dfb..11a1b942f1 100644
--- a/synapse/storage/background_updates.py
+++ b/synapse/storage/background_updates.py
@@ -80,11 +80,12 @@ class BackgroundUpdateStore(SQLBaseStore):
     BACKGROUND_UPDATE_INTERVAL_MS = 1000
     BACKGROUND_UPDATE_DURATION_MS = 100
 
-    def __init__(self, hs):
-        super(BackgroundUpdateStore, self).__init__(hs)
+    def __init__(self, db_conn, hs):
+        super(BackgroundUpdateStore, self).__init__(db_conn, hs)
         self._background_update_performance = {}
         self._background_update_queue = []
         self._background_update_handlers = {}
+        self._all_done = False
 
     @defer.inlineCallbacks
     def start_doing_background_updates(self):
@@ -98,7 +99,7 @@ class BackgroundUpdateStore(SQLBaseStore):
                 result = yield self.do_next_background_update(
                     self.BACKGROUND_UPDATE_DURATION_MS
                 )
-            except:
+            except Exception:
                 logger.exception("Error doing update")
             else:
                 if result is None:
@@ -106,9 +107,41 @@ class BackgroundUpdateStore(SQLBaseStore):
                         "No more background updates to do."
                         " Unscheduling background update task."
                     )
+                    self._all_done = True
                     defer.returnValue(None)
 
     @defer.inlineCallbacks
+    def has_completed_background_updates(self):
+        """Check if all the background updates have completed
+
+        Returns:
+            Deferred[bool]: True if all background updates have completed
+        """
+        # if we've previously determined that there is nothing left to do, that
+        # is easy
+        if self._all_done:
+            defer.returnValue(True)
+
+        # obviously, if we have things in our queue, we're not done.
+        if self._background_update_queue:
+            defer.returnValue(False)
+
+        # otherwise, check if there are updates to be run. This is important,
+        # as we may be running on a worker which doesn't perform the bg updates
+        # itself, but still wants to wait for them to happen.
+        updates = yield self._simple_select_onecol(
+            "background_updates",
+            keyvalues=None,
+            retcol="1",
+            desc="check_background_updates",
+        )
+        if not updates:
+            self._all_done = True
+            defer.returnValue(True)
+
+        defer.returnValue(False)
+
+    @defer.inlineCallbacks
     def do_next_background_update(self, desired_duration_ms):
         """Does some amount of work on the next queued background update
 
@@ -269,7 +302,7 @@ class BackgroundUpdateStore(SQLBaseStore):
             # Sqlite doesn't support concurrent creation of indexes.
             #
             # We don't use partial indices on SQLite as it wasn't introduced
-            # until 3.8, and wheezy has 3.7
+            # until 3.8, and wheezy and CentOS 7 have 3.7
             #
             # We assume that sqlite doesn't give us invalid indices; however
             # we may still end up with the index existing but the
diff --git a/synapse/storage/client_ips.py b/synapse/storage/client_ips.py
index 3c95e90eca..a03d1d6104 100644
--- a/synapse/storage/client_ips.py
+++ b/synapse/storage/client_ips.py
@@ -32,14 +32,14 @@ LAST_SEEN_GRANULARITY = 120 * 1000
 
 
 class ClientIpStore(background_updates.BackgroundUpdateStore):
-    def __init__(self, hs):
+    def __init__(self, db_conn, hs):
         self.client_ip_last_seen = Cache(
             name="client_ip_last_seen",
             keylen=4,
             max_entries=50000 * CACHE_SIZE_FACTOR,
         )
 
-        super(ClientIpStore, self).__init__(hs)
+        super(ClientIpStore, self).__init__(db_conn, hs)
 
         self.register_background_index_update(
             "user_ips_device_index",
diff --git a/synapse/storage/deviceinbox.py b/synapse/storage/deviceinbox.py
index 0b62b493d5..548e795daf 100644
--- a/synapse/storage/deviceinbox.py
+++ b/synapse/storage/deviceinbox.py
@@ -29,8 +29,8 @@ logger = logging.getLogger(__name__)
 class DeviceInboxStore(BackgroundUpdateStore):
     DEVICE_INBOX_STREAM_ID = "device_inbox_stream_drop"
 
-    def __init__(self, hs):
-        super(DeviceInboxStore, self).__init__(hs)
+    def __init__(self, db_conn, hs):
+        super(DeviceInboxStore, self).__init__(db_conn, hs)
 
         self.register_background_index_update(
             "device_inbox_stream_index",
diff --git a/synapse/storage/devices.py b/synapse/storage/devices.py
index bb27fd1f70..bd2effdf34 100644
--- a/synapse/storage/devices.py
+++ b/synapse/storage/devices.py
@@ -26,8 +26,8 @@ logger = logging.getLogger(__name__)
 
 
 class DeviceStore(SQLBaseStore):
-    def __init__(self, hs):
-        super(DeviceStore, self).__init__(hs)
+    def __init__(self, db_conn, hs):
+        super(DeviceStore, self).__init__(db_conn, hs)
 
         # Map of (user_id, device_id) -> bool. If there is an entry that implies
         # the device exists.
diff --git a/synapse/storage/event_federation.py b/synapse/storage/event_federation.py
index e8133de2fa..55a05c59d5 100644
--- a/synapse/storage/event_federation.py
+++ b/synapse/storage/event_federation.py
@@ -39,8 +39,8 @@ class EventFederationStore(SQLBaseStore):
 
     EVENT_AUTH_STATE_ONLY = "event_auth_state_only"
 
-    def __init__(self, hs):
-        super(EventFederationStore, self).__init__(hs)
+    def __init__(self, db_conn, hs):
+        super(EventFederationStore, self).__init__(db_conn, hs)
 
         self.register_background_update_handler(
             self.EVENT_AUTH_STATE_ONLY,
diff --git a/synapse/storage/event_push_actions.py b/synapse/storage/event_push_actions.py
index d6d8723b4a..8efe2fd4bb 100644
--- a/synapse/storage/event_push_actions.py
+++ b/synapse/storage/event_push_actions.py
@@ -65,8 +65,8 @@ def _deserialize_action(actions, is_highlight):
 class EventPushActionsStore(SQLBaseStore):
     EPA_HIGHLIGHT_INDEX = "epa_highlight_index"
 
-    def __init__(self, hs):
-        super(EventPushActionsStore, self).__init__(hs)
+    def __init__(self, db_conn, hs):
+        super(EventPushActionsStore, self).__init__(db_conn, hs)
 
         self.register_background_index_update(
             self.EPA_HIGHLIGHT_INDEX,
diff --git a/synapse/storage/events.py b/synapse/storage/events.py
index 7002b3752e..d08f7571d7 100644
--- a/synapse/storage/events.py
+++ b/synapse/storage/events.py
@@ -21,7 +21,7 @@ from synapse.events.utils import prune_event
 
 from synapse.util.async import ObservableDeferred
 from synapse.util.logcontext import (
-    preserve_fn, PreserveLoggingContext, preserve_context_over_deferred
+    preserve_fn, PreserveLoggingContext, make_deferred_yieldable
 )
 from synapse.util.logutils import log_function
 from synapse.util.metrics import Measure
@@ -88,13 +88,23 @@ class _EventPeristenceQueue(object):
     def add_to_queue(self, room_id, events_and_contexts, backfilled):
         """Add events to the queue, with the given persist_event options.
 
+        NB: due to the normal usage pattern of this method, it does *not*
+        follow the synapse logcontext rules, and leaves the logcontext in
+        place whether or not the returned deferred is ready.
+
         Args:
             room_id (str):
             events_and_contexts (list[(EventBase, EventContext)]):
             backfilled (bool):
+
+        Returns:
+            defer.Deferred: a deferred which will resolve once the events are
+                persisted. Runs its callbacks *without* a logcontext.
         """
         queue = self._event_persist_queues.setdefault(room_id, deque())
         if queue:
+            # if the last item in the queue has the same `backfilled` setting,
+            # we can just add these new events to that item.
             end_item = queue[-1]
             if end_item.backfilled == backfilled:
                 end_item.events_and_contexts.extend(events_and_contexts)
@@ -113,11 +123,11 @@ class _EventPeristenceQueue(object):
     def handle_queue(self, room_id, per_item_callback):
         """Attempts to handle the queue for a room if not already being handled.
 
-        The given callback will be invoked with for each item in the queue,1
+        The given callback will be invoked with for each item in the queue,
         of type _EventPersistQueueItem. The per_item_callback will continuously
         be called with new items, unless the queue becomnes empty. The return
         value of the function will be given to the deferreds waiting on the item,
-        exceptions will be passed to the deferres as well.
+        exceptions will be passed to the deferreds as well.
 
         This function should therefore be called whenever anything is added
         to the queue.
@@ -187,8 +197,8 @@ class EventsStore(SQLBaseStore):
     EVENT_ORIGIN_SERVER_TS_NAME = "event_origin_server_ts"
     EVENT_FIELDS_SENDER_URL_UPDATE_NAME = "event_fields_sender_url"
 
-    def __init__(self, hs):
-        super(EventsStore, self).__init__(hs)
+    def __init__(self, db_conn, hs):
+        super(EventsStore, self).__init__(db_conn, hs)
         self._clock = hs.get_clock()
         self.register_background_update_handler(
             self.EVENT_ORIGIN_SERVER_TS_NAME, self._background_reindex_origin_server_ts
@@ -233,7 +243,7 @@ class EventsStore(SQLBaseStore):
 
         deferreds = []
         for room_id, evs_ctxs in partitioned.iteritems():
-            d = preserve_fn(self._event_persist_queue.add_to_queue)(
+            d = self._event_persist_queue.add_to_queue(
                 room_id, evs_ctxs,
                 backfilled=backfilled,
             )
@@ -242,7 +252,7 @@ class EventsStore(SQLBaseStore):
         for room_id in partitioned:
             self._maybe_start_persisting(room_id)
 
-        return preserve_context_over_deferred(
+        return make_deferred_yieldable(
             defer.gatherResults(deferreds, consumeErrors=True)
         )
 
@@ -267,7 +277,7 @@ class EventsStore(SQLBaseStore):
 
         self._maybe_start_persisting(event.room_id)
 
-        yield preserve_context_over_deferred(deferred)
+        yield make_deferred_yieldable(deferred)
 
         max_persisted_id = yield self._stream_id_gen.get_current_token()
         defer.returnValue((event.internal_metadata.stream_ordering, max_persisted_id))
@@ -784,6 +794,9 @@ class EventsStore(SQLBaseStore):
                     self._invalidate_cache_and_stream(
                         txn, self.is_host_joined, (room_id, host)
                     )
+                    self._invalidate_cache_and_stream(
+                        txn, self.was_host_joined, (room_id, host)
+                    )
 
                 self._invalidate_cache_and_stream(
                     txn, self.get_users_in_room, (room_id,)
@@ -1468,7 +1481,7 @@ class EventsStore(SQLBaseStore):
                                         for i in ids
                                         if i in res
                                     ])
-                            except:
+                            except Exception:
                                 logger.exception("Failed to callback")
                 with PreserveLoggingContext():
                     reactor.callFromThread(fire, event_list, row_dict)
@@ -1523,7 +1536,7 @@ class EventsStore(SQLBaseStore):
         if not allow_rejected:
             rows[:] = [r for r in rows if not r["rejects"]]
 
-        res = yield preserve_context_over_deferred(defer.gatherResults(
+        res = yield make_deferred_yieldable(defer.gatherResults(
             [
                 preserve_fn(self._get_event_from_row)(
                     row["internal_metadata"], row["json"], row["redacts"],
diff --git a/synapse/storage/group_server.py b/synapse/storage/group_server.py
new file mode 100644
index 0000000000..8fde1aab8e
--- /dev/null
+++ b/synapse/storage/group_server.py
@@ -0,0 +1,1233 @@
+# -*- coding: utf-8 -*-
+# Copyright 2017 Vector Creations Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from twisted.internet import defer
+
+from synapse.api.errors import SynapseError
+
+from ._base import SQLBaseStore
+
+import ujson as json
+
+
+# The category ID for the "default" category. We don't store as null in the
+# database to avoid the fun of null != null
+_DEFAULT_CATEGORY_ID = ""
+_DEFAULT_ROLE_ID = ""
+
+
+class GroupServerStore(SQLBaseStore):
+    def get_group(self, group_id):
+        return self._simple_select_one(
+            table="groups",
+            keyvalues={
+                "group_id": group_id,
+            },
+            retcols=(
+                "name", "short_description", "long_description", "avatar_url", "is_public"
+            ),
+            allow_none=True,
+            desc="is_user_in_group",
+        )
+
+    def get_users_in_group(self, group_id, include_private=False):
+        # TODO: Pagination
+
+        keyvalues = {
+            "group_id": group_id,
+        }
+        if not include_private:
+            keyvalues["is_public"] = True
+
+        return self._simple_select_list(
+            table="group_users",
+            keyvalues=keyvalues,
+            retcols=("user_id", "is_public", "is_admin",),
+            desc="get_users_in_group",
+        )
+
+    def get_invited_users_in_group(self, group_id):
+        # TODO: Pagination
+
+        return self._simple_select_onecol(
+            table="group_invites",
+            keyvalues={
+                "group_id": group_id,
+            },
+            retcol="user_id",
+            desc="get_invited_users_in_group",
+        )
+
+    def get_rooms_in_group(self, group_id, include_private=False):
+        # TODO: Pagination
+
+        keyvalues = {
+            "group_id": group_id,
+        }
+        if not include_private:
+            keyvalues["is_public"] = True
+
+        return self._simple_select_list(
+            table="group_rooms",
+            keyvalues=keyvalues,
+            retcols=("room_id", "is_public",),
+            desc="get_rooms_in_group",
+        )
+
+    def get_rooms_for_summary_by_category(self, group_id, include_private=False):
+        """Get the rooms and categories that should be included in a summary request
+
+        Returns ([rooms], [categories])
+        """
+        def _get_rooms_for_summary_txn(txn):
+            keyvalues = {
+                "group_id": group_id,
+            }
+            if not include_private:
+                keyvalues["is_public"] = True
+
+            sql = """
+                SELECT room_id, is_public, category_id, room_order
+                FROM group_summary_rooms
+                WHERE group_id = ?
+            """
+
+            if not include_private:
+                sql += " AND is_public = ?"
+                txn.execute(sql, (group_id, True))
+            else:
+                txn.execute(sql, (group_id,))
+
+            rooms = [
+                {
+                    "room_id": row[0],
+                    "is_public": row[1],
+                    "category_id": row[2] if row[2] != _DEFAULT_CATEGORY_ID else None,
+                    "order": row[3],
+                }
+                for row in txn
+            ]
+
+            sql = """
+                SELECT category_id, is_public, profile, cat_order
+                FROM group_summary_room_categories
+                INNER JOIN group_room_categories USING (group_id, category_id)
+                WHERE group_id = ?
+            """
+
+            if not include_private:
+                sql += " AND is_public = ?"
+                txn.execute(sql, (group_id, True))
+            else:
+                txn.execute(sql, (group_id,))
+
+            categories = {
+                row[0]: {
+                    "is_public": row[1],
+                    "profile": json.loads(row[2]),
+                    "order": row[3],
+                }
+                for row in txn
+            }
+
+            return rooms, categories
+        return self.runInteraction(
+            "get_rooms_for_summary", _get_rooms_for_summary_txn
+        )
+
+    def add_room_to_summary(self, group_id, room_id, category_id, order, is_public):
+        return self.runInteraction(
+            "add_room_to_summary", self._add_room_to_summary_txn,
+            group_id, room_id, category_id, order, is_public,
+        )
+
+    def _add_room_to_summary_txn(self, txn, group_id, room_id, category_id, order,
+                                 is_public):
+        """Add (or update) room's entry in summary.
+
+        Args:
+            group_id (str)
+            room_id (str)
+            category_id (str): If not None then adds the category to the end of
+                the summary if its not already there. [Optional]
+            order (int): If not None inserts the room at that position, e.g.
+                an order of 1 will put the room first. Otherwise, the room gets
+                added to the end.
+        """
+        room_in_group = self._simple_select_one_onecol_txn(
+            txn,
+            table="group_rooms",
+            keyvalues={
+                "group_id": group_id,
+                "room_id": room_id,
+            },
+            retcol="room_id",
+            allow_none=True,
+        )
+        if not room_in_group:
+            raise SynapseError(400, "room not in group")
+
+        if category_id is None:
+            category_id = _DEFAULT_CATEGORY_ID
+        else:
+            cat_exists = self._simple_select_one_onecol_txn(
+                txn,
+                table="group_room_categories",
+                keyvalues={
+                    "group_id": group_id,
+                    "category_id": category_id,
+                },
+                retcol="group_id",
+                allow_none=True,
+            )
+            if not cat_exists:
+                raise SynapseError(400, "Category doesn't exist")
+
+            # TODO: Check category is part of summary already
+            cat_exists = self._simple_select_one_onecol_txn(
+                txn,
+                table="group_summary_room_categories",
+                keyvalues={
+                    "group_id": group_id,
+                    "category_id": category_id,
+                },
+                retcol="group_id",
+                allow_none=True,
+            )
+            if not cat_exists:
+                # If not, add it with an order larger than all others
+                txn.execute("""
+                    INSERT INTO group_summary_room_categories
+                    (group_id, category_id, cat_order)
+                    SELECT ?, ?, COALESCE(MAX(cat_order), 0) + 1
+                    FROM group_summary_room_categories
+                    WHERE group_id = ? AND category_id = ?
+                """, (group_id, category_id, group_id, category_id))
+
+        existing = self._simple_select_one_txn(
+            txn,
+            table="group_summary_rooms",
+            keyvalues={
+                "group_id": group_id,
+                "room_id": room_id,
+                "category_id": category_id,
+            },
+            retcols=("room_order", "is_public",),
+            allow_none=True,
+        )
+
+        if order is not None:
+            # Shuffle other room orders that come after the given order
+            sql = """
+                UPDATE group_summary_rooms SET room_order = room_order + 1
+                WHERE group_id = ? AND category_id = ? AND room_order >= ?
+            """
+            txn.execute(sql, (group_id, category_id, order,))
+        elif not existing:
+            sql = """
+                SELECT COALESCE(MAX(room_order), 0) + 1 FROM group_summary_rooms
+                WHERE group_id = ? AND category_id = ?
+            """
+            txn.execute(sql, (group_id, category_id,))
+            order, = txn.fetchone()
+
+        if existing:
+            to_update = {}
+            if order is not None:
+                to_update["room_order"] = order
+            if is_public is not None:
+                to_update["is_public"] = is_public
+            self._simple_update_txn(
+                txn,
+                table="group_summary_rooms",
+                keyvalues={
+                    "group_id": group_id,
+                    "category_id": category_id,
+                    "room_id": room_id,
+                },
+                values=to_update,
+            )
+        else:
+            if is_public is None:
+                is_public = True
+
+            self._simple_insert_txn(
+                txn,
+                table="group_summary_rooms",
+                values={
+                    "group_id": group_id,
+                    "category_id": category_id,
+                    "room_id": room_id,
+                    "room_order": order,
+                    "is_public": is_public,
+                },
+            )
+
+    def remove_room_from_summary(self, group_id, room_id, category_id):
+        if category_id is None:
+            category_id = _DEFAULT_CATEGORY_ID
+
+        return self._simple_delete(
+            table="group_summary_rooms",
+            keyvalues={
+                "group_id": group_id,
+                "category_id": category_id,
+                "room_id": room_id,
+            },
+            desc="remove_room_from_summary",
+        )
+
+    @defer.inlineCallbacks
+    def get_group_categories(self, group_id):
+        rows = yield self._simple_select_list(
+            table="group_room_categories",
+            keyvalues={
+                "group_id": group_id,
+            },
+            retcols=("category_id", "is_public", "profile"),
+            desc="get_group_categories",
+        )
+
+        defer.returnValue({
+            row["category_id"]: {
+                "is_public": row["is_public"],
+                "profile": json.loads(row["profile"]),
+            }
+            for row in rows
+        })
+
+    @defer.inlineCallbacks
+    def get_group_category(self, group_id, category_id):
+        category = yield self._simple_select_one(
+            table="group_room_categories",
+            keyvalues={
+                "group_id": group_id,
+                "category_id": category_id,
+            },
+            retcols=("is_public", "profile"),
+            desc="get_group_category",
+        )
+
+        category["profile"] = json.loads(category["profile"])
+
+        defer.returnValue(category)
+
+    def upsert_group_category(self, group_id, category_id, profile, is_public):
+        """Add/update room category for group
+        """
+        insertion_values = {}
+        update_values = {"category_id": category_id}  # This cannot be empty
+
+        if profile is None:
+            insertion_values["profile"] = "{}"
+        else:
+            update_values["profile"] = json.dumps(profile)
+
+        if is_public is None:
+            insertion_values["is_public"] = True
+        else:
+            update_values["is_public"] = is_public
+
+        return self._simple_upsert(
+            table="group_room_categories",
+            keyvalues={
+                "group_id": group_id,
+                "category_id": category_id,
+            },
+            values=update_values,
+            insertion_values=insertion_values,
+            desc="upsert_group_category",
+        )
+
+    def remove_group_category(self, group_id, category_id):
+        return self._simple_delete(
+            table="group_room_categories",
+            keyvalues={
+                "group_id": group_id,
+                "category_id": category_id,
+            },
+            desc="remove_group_category",
+        )
+
+    @defer.inlineCallbacks
+    def get_group_roles(self, group_id):
+        rows = yield self._simple_select_list(
+            table="group_roles",
+            keyvalues={
+                "group_id": group_id,
+            },
+            retcols=("role_id", "is_public", "profile"),
+            desc="get_group_roles",
+        )
+
+        defer.returnValue({
+            row["role_id"]: {
+                "is_public": row["is_public"],
+                "profile": json.loads(row["profile"]),
+            }
+            for row in rows
+        })
+
+    @defer.inlineCallbacks
+    def get_group_role(self, group_id, role_id):
+        role = yield self._simple_select_one(
+            table="group_roles",
+            keyvalues={
+                "group_id": group_id,
+                "role_id": role_id,
+            },
+            retcols=("is_public", "profile"),
+            desc="get_group_role",
+        )
+
+        role["profile"] = json.loads(role["profile"])
+
+        defer.returnValue(role)
+
+    def upsert_group_role(self, group_id, role_id, profile, is_public):
+        """Add/remove user role
+        """
+        insertion_values = {}
+        update_values = {"role_id": role_id}  # This cannot be empty
+
+        if profile is None:
+            insertion_values["profile"] = "{}"
+        else:
+            update_values["profile"] = json.dumps(profile)
+
+        if is_public is None:
+            insertion_values["is_public"] = True
+        else:
+            update_values["is_public"] = is_public
+
+        return self._simple_upsert(
+            table="group_roles",
+            keyvalues={
+                "group_id": group_id,
+                "role_id": role_id,
+            },
+            values=update_values,
+            insertion_values=insertion_values,
+            desc="upsert_group_role",
+        )
+
+    def remove_group_role(self, group_id, role_id):
+        return self._simple_delete(
+            table="group_roles",
+            keyvalues={
+                "group_id": group_id,
+                "role_id": role_id,
+            },
+            desc="remove_group_role",
+        )
+
+    def add_user_to_summary(self, group_id, user_id, role_id, order, is_public):
+        return self.runInteraction(
+            "add_user_to_summary", self._add_user_to_summary_txn,
+            group_id, user_id, role_id, order, is_public,
+        )
+
+    def _add_user_to_summary_txn(self, txn, group_id, user_id, role_id, order,
+                                 is_public):
+        """Add (or update) user's entry in summary.
+
+        Args:
+            group_id (str)
+            user_id (str)
+            role_id (str): If not None then adds the role to the end of
+                the summary if its not already there. [Optional]
+            order (int): If not None inserts the user at that position, e.g.
+                an order of 1 will put the user first. Otherwise, the user gets
+                added to the end.
+        """
+        user_in_group = self._simple_select_one_onecol_txn(
+            txn,
+            table="group_users",
+            keyvalues={
+                "group_id": group_id,
+                "user_id": user_id,
+            },
+            retcol="user_id",
+            allow_none=True,
+        )
+        if not user_in_group:
+            raise SynapseError(400, "user not in group")
+
+        if role_id is None:
+            role_id = _DEFAULT_ROLE_ID
+        else:
+            role_exists = self._simple_select_one_onecol_txn(
+                txn,
+                table="group_roles",
+                keyvalues={
+                    "group_id": group_id,
+                    "role_id": role_id,
+                },
+                retcol="group_id",
+                allow_none=True,
+            )
+            if not role_exists:
+                raise SynapseError(400, "Role doesn't exist")
+
+            # TODO: Check role is part of the summary already
+            role_exists = self._simple_select_one_onecol_txn(
+                txn,
+                table="group_summary_roles",
+                keyvalues={
+                    "group_id": group_id,
+                    "role_id": role_id,
+                },
+                retcol="group_id",
+                allow_none=True,
+            )
+            if not role_exists:
+                # If not, add it with an order larger than all others
+                txn.execute("""
+                    INSERT INTO group_summary_roles
+                    (group_id, role_id, role_order)
+                    SELECT ?, ?, COALESCE(MAX(role_order), 0) + 1
+                    FROM group_summary_roles
+                    WHERE group_id = ? AND role_id = ?
+                """, (group_id, role_id, group_id, role_id))
+
+        existing = self._simple_select_one_txn(
+            txn,
+            table="group_summary_users",
+            keyvalues={
+                "group_id": group_id,
+                "user_id": user_id,
+                "role_id": role_id,
+            },
+            retcols=("user_order", "is_public",),
+            allow_none=True,
+        )
+
+        if order is not None:
+            # Shuffle other users orders that come after the given order
+            sql = """
+                UPDATE group_summary_users SET user_order = user_order + 1
+                WHERE group_id = ? AND role_id = ? AND user_order >= ?
+            """
+            txn.execute(sql, (group_id, role_id, order,))
+        elif not existing:
+            sql = """
+                SELECT COALESCE(MAX(user_order), 0) + 1 FROM group_summary_users
+                WHERE group_id = ? AND role_id = ?
+            """
+            txn.execute(sql, (group_id, role_id,))
+            order, = txn.fetchone()
+
+        if existing:
+            to_update = {}
+            if order is not None:
+                to_update["user_order"] = order
+            if is_public is not None:
+                to_update["is_public"] = is_public
+            self._simple_update_txn(
+                txn,
+                table="group_summary_users",
+                keyvalues={
+                    "group_id": group_id,
+                    "role_id": role_id,
+                    "user_id": user_id,
+                },
+                values=to_update,
+            )
+        else:
+            if is_public is None:
+                is_public = True
+
+            self._simple_insert_txn(
+                txn,
+                table="group_summary_users",
+                values={
+                    "group_id": group_id,
+                    "role_id": role_id,
+                    "user_id": user_id,
+                    "user_order": order,
+                    "is_public": is_public,
+                },
+            )
+
+    def remove_user_from_summary(self, group_id, user_id, role_id):
+        if role_id is None:
+            role_id = _DEFAULT_ROLE_ID
+
+        return self._simple_delete(
+            table="group_summary_users",
+            keyvalues={
+                "group_id": group_id,
+                "role_id": role_id,
+                "user_id": user_id,
+            },
+            desc="remove_user_from_summary",
+        )
+
+    def get_users_for_summary_by_role(self, group_id, include_private=False):
+        """Get the users and roles that should be included in a summary request
+
+        Returns ([users], [roles])
+        """
+        def _get_users_for_summary_txn(txn):
+            keyvalues = {
+                "group_id": group_id,
+            }
+            if not include_private:
+                keyvalues["is_public"] = True
+
+            sql = """
+                SELECT user_id, is_public, role_id, user_order
+                FROM group_summary_users
+                WHERE group_id = ?
+            """
+
+            if not include_private:
+                sql += " AND is_public = ?"
+                txn.execute(sql, (group_id, True))
+            else:
+                txn.execute(sql, (group_id,))
+
+            users = [
+                {
+                    "user_id": row[0],
+                    "is_public": row[1],
+                    "role_id": row[2] if row[2] != _DEFAULT_ROLE_ID else None,
+                    "order": row[3],
+                }
+                for row in txn
+            ]
+
+            sql = """
+                SELECT role_id, is_public, profile, role_order
+                FROM group_summary_roles
+                INNER JOIN group_roles USING (group_id, role_id)
+                WHERE group_id = ?
+            """
+
+            if not include_private:
+                sql += " AND is_public = ?"
+                txn.execute(sql, (group_id, True))
+            else:
+                txn.execute(sql, (group_id,))
+
+            roles = {
+                row[0]: {
+                    "is_public": row[1],
+                    "profile": json.loads(row[2]),
+                    "order": row[3],
+                }
+                for row in txn
+            }
+
+            return users, roles
+        return self.runInteraction(
+            "get_users_for_summary_by_role", _get_users_for_summary_txn
+        )
+
+    def is_user_in_group(self, user_id, group_id):
+        return self._simple_select_one_onecol(
+            table="group_users",
+            keyvalues={
+                "group_id": group_id,
+                "user_id": user_id,
+            },
+            retcol="user_id",
+            allow_none=True,
+            desc="is_user_in_group",
+        ).addCallback(lambda r: bool(r))
+
+    def is_user_admin_in_group(self, group_id, user_id):
+        return self._simple_select_one_onecol(
+            table="group_users",
+            keyvalues={
+                "group_id": group_id,
+                "user_id": user_id,
+            },
+            retcol="is_admin",
+            allow_none=True,
+            desc="is_user_admin_in_group",
+        )
+
+    def add_group_invite(self, group_id, user_id):
+        """Record that the group server has invited a user
+        """
+        return self._simple_insert(
+            table="group_invites",
+            values={
+                "group_id": group_id,
+                "user_id": user_id,
+            },
+            desc="add_group_invite",
+        )
+
+    def is_user_invited_to_local_group(self, group_id, user_id):
+        """Has the group server invited a user?
+        """
+        return self._simple_select_one_onecol(
+            table="group_invites",
+            keyvalues={
+                "group_id": group_id,
+                "user_id": user_id,
+            },
+            retcol="user_id",
+            desc="is_user_invited_to_local_group",
+            allow_none=True,
+        )
+
+    def get_users_membership_info_in_group(self, group_id, user_id):
+        """Get a dict describing the membership of a user in a group.
+
+        Example if joined:
+
+            {
+                "membership": "join",
+                "is_public": True,
+                "is_privileged": False,
+            }
+
+        Returns an empty dict if the user is not join/invite/etc
+        """
+        def _get_users_membership_in_group_txn(txn):
+            row = self._simple_select_one_txn(
+                txn,
+                table="group_users",
+                keyvalues={
+                    "group_id": group_id,
+                    "user_id": user_id,
+                },
+                retcols=("is_admin", "is_public"),
+                allow_none=True,
+            )
+
+            if row:
+                return {
+                    "membership": "join",
+                    "is_public": row["is_public"],
+                    "is_privileged": row["is_admin"],
+                }
+
+            row = self._simple_select_one_onecol_txn(
+                txn,
+                table="group_invites",
+                keyvalues={
+                    "group_id": group_id,
+                    "user_id": user_id,
+                },
+                retcol="user_id",
+                allow_none=True,
+            )
+
+            if row:
+                return {
+                    "membership": "invite",
+                }
+
+            return {}
+
+        return self.runInteraction(
+            "get_users_membership_info_in_group", _get_users_membership_in_group_txn,
+        )
+
+    def add_user_to_group(self, group_id, user_id, is_admin=False, is_public=True,
+                          local_attestation=None, remote_attestation=None):
+        """Add a user to the group server.
+
+        Args:
+            group_id (str)
+            user_id (str)
+            is_admin (bool)
+            is_public (bool)
+            local_attestation (dict): The attestation the GS created to give
+                to the remote server. Optional if the user and group are on the
+                same server
+            remote_attestation (dict): The attestation given to GS by remote
+                server. Optional if the user and group are on the same server
+        """
+        def _add_user_to_group_txn(txn):
+            self._simple_insert_txn(
+                txn,
+                table="group_users",
+                values={
+                    "group_id": group_id,
+                    "user_id": user_id,
+                    "is_admin": is_admin,
+                    "is_public": is_public,
+                },
+            )
+
+            self._simple_delete_txn(
+                txn,
+                table="group_invites",
+                keyvalues={
+                    "group_id": group_id,
+                    "user_id": user_id,
+                },
+            )
+
+            if local_attestation:
+                self._simple_insert_txn(
+                    txn,
+                    table="group_attestations_renewals",
+                    values={
+                        "group_id": group_id,
+                        "user_id": user_id,
+                        "valid_until_ms": local_attestation["valid_until_ms"],
+                    },
+                )
+            if remote_attestation:
+                self._simple_insert_txn(
+                    txn,
+                    table="group_attestations_remote",
+                    values={
+                        "group_id": group_id,
+                        "user_id": user_id,
+                        "valid_until_ms": remote_attestation["valid_until_ms"],
+                        "attestation_json": json.dumps(remote_attestation),
+                    },
+                )
+
+        return self.runInteraction(
+            "add_user_to_group", _add_user_to_group_txn
+        )
+
+    def remove_user_from_group(self, group_id, user_id):
+        def _remove_user_from_group_txn(txn):
+            self._simple_delete_txn(
+                txn,
+                table="group_users",
+                keyvalues={
+                    "group_id": group_id,
+                    "user_id": user_id,
+                },
+            )
+            self._simple_delete_txn(
+                txn,
+                table="group_invites",
+                keyvalues={
+                    "group_id": group_id,
+                    "user_id": user_id,
+                },
+            )
+            self._simple_delete_txn(
+                txn,
+                table="group_attestations_renewals",
+                keyvalues={
+                    "group_id": group_id,
+                    "user_id": user_id,
+                },
+            )
+            self._simple_delete_txn(
+                txn,
+                table="group_attestations_remote",
+                keyvalues={
+                    "group_id": group_id,
+                    "user_id": user_id,
+                },
+            )
+            self._simple_delete_txn(
+                txn,
+                table="group_summary_users",
+                keyvalues={
+                    "group_id": group_id,
+                    "user_id": user_id,
+                },
+            )
+        return self.runInteraction("remove_user_from_group", _remove_user_from_group_txn)
+
+    def add_room_to_group(self, group_id, room_id, is_public):
+        return self._simple_insert(
+            table="group_rooms",
+            values={
+                "group_id": group_id,
+                "room_id": room_id,
+                "is_public": is_public,
+            },
+            desc="add_room_to_group",
+        )
+
+    def update_room_in_group_visibility(self, group_id, room_id, is_public):
+        return self._simple_update(
+            table="group_rooms",
+            keyvalues={
+                "group_id": group_id,
+                "room_id": room_id,
+            },
+            updatevalues={
+                "is_public": is_public,
+            },
+            desc="update_room_in_group_visibility",
+        )
+
+    def remove_room_from_group(self, group_id, room_id):
+        def _remove_room_from_group_txn(txn):
+            self._simple_delete_txn(
+                txn,
+                table="group_rooms",
+                keyvalues={
+                    "group_id": group_id,
+                    "room_id": room_id,
+                },
+            )
+
+            self._simple_delete_txn(
+                txn,
+                table="group_summary_rooms",
+                keyvalues={
+                    "group_id": group_id,
+                    "room_id": room_id,
+                },
+            )
+        return self.runInteraction(
+            "remove_room_from_group", _remove_room_from_group_txn,
+        )
+
+    def get_publicised_groups_for_user(self, user_id):
+        """Get all groups a user is publicising
+        """
+        return self._simple_select_onecol(
+            table="local_group_membership",
+            keyvalues={
+                "user_id": user_id,
+                "membership": "join",
+                "is_publicised": True,
+            },
+            retcol="group_id",
+            desc="get_publicised_groups_for_user",
+        )
+
+    def update_group_publicity(self, group_id, user_id, publicise):
+        """Update whether the user is publicising their membership of the group
+        """
+        return self._simple_update_one(
+            table="local_group_membership",
+            keyvalues={
+                "group_id": group_id,
+                "user_id": user_id,
+            },
+            updatevalues={
+                "is_publicised": publicise,
+            },
+            desc="update_group_publicity"
+        )
+
+    @defer.inlineCallbacks
+    def register_user_group_membership(self, group_id, user_id, membership,
+                                       is_admin=False, content={},
+                                       local_attestation=None,
+                                       remote_attestation=None,
+                                       is_publicised=False,
+                                       ):
+        """Registers that a local user is a member of a (local or remote) group.
+
+        Args:
+            group_id (str)
+            user_id (str)
+            membership (str)
+            is_admin (bool)
+            content (dict): Content of the membership, e.g. includes the inviter
+                if the user has been invited.
+            local_attestation (dict): If remote group then store the fact that we
+                have given out an attestation, else None.
+            remote_attestation (dict): If remote group then store the remote
+                attestation from the group, else None.
+        """
+        def _register_user_group_membership_txn(txn, next_id):
+            # TODO: Upsert?
+            self._simple_delete_txn(
+                txn,
+                table="local_group_membership",
+                keyvalues={
+                    "group_id": group_id,
+                    "user_id": user_id,
+                },
+            )
+            self._simple_insert_txn(
+                txn,
+                table="local_group_membership",
+                values={
+                    "group_id": group_id,
+                    "user_id": user_id,
+                    "is_admin": is_admin,
+                    "membership": membership,
+                    "is_publicised": is_publicised,
+                    "content": json.dumps(content),
+                },
+            )
+
+            self._simple_insert_txn(
+                txn,
+                table="local_group_updates",
+                values={
+                    "stream_id": next_id,
+                    "group_id": group_id,
+                    "user_id": user_id,
+                    "type": "membership",
+                    "content": json.dumps({"membership": membership, "content": content}),
+                }
+            )
+            self._group_updates_stream_cache.entity_has_changed(user_id, next_id)
+
+            # TODO: Insert profile to ensure it comes down stream if its a join.
+
+            if membership == "join":
+                if local_attestation:
+                    self._simple_insert_txn(
+                        txn,
+                        table="group_attestations_renewals",
+                        values={
+                            "group_id": group_id,
+                            "user_id": user_id,
+                            "valid_until_ms": local_attestation["valid_until_ms"],
+                        }
+                    )
+                if remote_attestation:
+                    self._simple_insert_txn(
+                        txn,
+                        table="group_attestations_remote",
+                        values={
+                            "group_id": group_id,
+                            "user_id": user_id,
+                            "valid_until_ms": remote_attestation["valid_until_ms"],
+                            "attestation_json": json.dumps(remote_attestation),
+                        }
+                    )
+            else:
+                self._simple_delete_txn(
+                    txn,
+                    table="group_attestations_renewals",
+                    keyvalues={
+                        "group_id": group_id,
+                        "user_id": user_id,
+                    },
+                )
+                self._simple_delete_txn(
+                    txn,
+                    table="group_attestations_remote",
+                    keyvalues={
+                        "group_id": group_id,
+                        "user_id": user_id,
+                    },
+                )
+
+            return next_id
+
+        with self._group_updates_id_gen.get_next() as next_id:
+            res = yield self.runInteraction(
+                "register_user_group_membership",
+                _register_user_group_membership_txn, next_id,
+            )
+        defer.returnValue(res)
+
+    @defer.inlineCallbacks
+    def create_group(self, group_id, user_id, name, avatar_url, short_description,
+                     long_description,):
+        yield self._simple_insert(
+            table="groups",
+            values={
+                "group_id": group_id,
+                "name": name,
+                "avatar_url": avatar_url,
+                "short_description": short_description,
+                "long_description": long_description,
+                "is_public": True,
+            },
+            desc="create_group",
+        )
+
+    @defer.inlineCallbacks
+    def update_group_profile(self, group_id, profile,):
+        yield self._simple_update_one(
+            table="groups",
+            keyvalues={
+                "group_id": group_id,
+            },
+            updatevalues=profile,
+            desc="update_group_profile",
+        )
+
+    def get_attestations_need_renewals(self, valid_until_ms):
+        """Get all attestations that need to be renewed until givent time
+        """
+        def _get_attestations_need_renewals_txn(txn):
+            sql = """
+                SELECT group_id, user_id FROM group_attestations_renewals
+                WHERE valid_until_ms <= ?
+            """
+            txn.execute(sql, (valid_until_ms,))
+            return self.cursor_to_dict(txn)
+        return self.runInteraction(
+            "get_attestations_need_renewals", _get_attestations_need_renewals_txn
+        )
+
+    def update_attestation_renewal(self, group_id, user_id, attestation):
+        """Update an attestation that we have renewed
+        """
+        return self._simple_update_one(
+            table="group_attestations_renewals",
+            keyvalues={
+                "group_id": group_id,
+                "user_id": user_id,
+            },
+            updatevalues={
+                "valid_until_ms": attestation["valid_until_ms"],
+            },
+            desc="update_attestation_renewal",
+        )
+
+    def update_remote_attestion(self, group_id, user_id, attestation):
+        """Update an attestation that a remote has renewed
+        """
+        return self._simple_update_one(
+            table="group_attestations_remote",
+            keyvalues={
+                "group_id": group_id,
+                "user_id": user_id,
+            },
+            updatevalues={
+                "valid_until_ms": attestation["valid_until_ms"],
+                "attestation_json": json.dumps(attestation)
+            },
+            desc="update_remote_attestion",
+        )
+
+    def remove_attestation_renewal(self, group_id, user_id):
+        """Remove an attestation that we thought we should renew, but actually
+        shouldn't. Ideally this would never get called as we would never
+        incorrectly try and do attestations for local users on local groups.
+
+        Args:
+            group_id (str)
+            user_id (str)
+        """
+        return self._simple_delete(
+            table="group_attestations_renewals",
+            keyvalues={
+                "group_id": group_id,
+                "user_id": user_id,
+            },
+            desc="remove_attestation_renewal",
+        )
+
+    @defer.inlineCallbacks
+    def get_remote_attestation(self, group_id, user_id):
+        """Get the attestation that proves the remote agrees that the user is
+        in the group.
+        """
+        row = yield self._simple_select_one(
+            table="group_attestations_remote",
+            keyvalues={
+                "group_id": group_id,
+                "user_id": user_id,
+            },
+            retcols=("valid_until_ms", "attestation_json"),
+            desc="get_remote_attestation",
+            allow_none=True,
+        )
+
+        now = int(self._clock.time_msec())
+        if row and now < row["valid_until_ms"]:
+            defer.returnValue(json.loads(row["attestation_json"]))
+
+        defer.returnValue(None)
+
+    def get_joined_groups(self, user_id):
+        return self._simple_select_onecol(
+            table="local_group_membership",
+            keyvalues={
+                "user_id": user_id,
+                "membership": "join",
+            },
+            retcol="group_id",
+            desc="get_joined_groups",
+        )
+
+    def get_all_groups_for_user(self, user_id, now_token):
+        def _get_all_groups_for_user_txn(txn):
+            sql = """
+                SELECT group_id, type, membership, u.content
+                FROM local_group_updates AS u
+                INNER JOIN local_group_membership USING (group_id, user_id)
+                WHERE user_id = ? AND membership != 'leave'
+                    AND stream_id <= ?
+            """
+            txn.execute(sql, (user_id, now_token,))
+            return [
+                {
+                    "group_id": row[0],
+                    "type": row[1],
+                    "membership": row[2],
+                    "content": json.loads(row[3]),
+                }
+                for row in txn
+            ]
+        return self.runInteraction(
+            "get_all_groups_for_user", _get_all_groups_for_user_txn,
+        )
+
+    def get_groups_changes_for_user(self, user_id, from_token, to_token):
+        from_token = int(from_token)
+        has_changed = self._group_updates_stream_cache.has_entity_changed(
+            user_id, from_token,
+        )
+        if not has_changed:
+            return []
+
+        def _get_groups_changes_for_user_txn(txn):
+            sql = """
+                SELECT group_id, membership, type, u.content
+                FROM local_group_updates AS u
+                INNER JOIN local_group_membership USING (group_id, user_id)
+                WHERE user_id = ? AND ? < stream_id AND stream_id <= ?
+            """
+            txn.execute(sql, (user_id, from_token, to_token,))
+            return [{
+                "group_id": group_id,
+                "membership": membership,
+                "type": gtype,
+                "content": json.loads(content_json),
+            } for group_id, membership, gtype, content_json in txn]
+        return self.runInteraction(
+            "get_groups_changes_for_user", _get_groups_changes_for_user_txn,
+        )
+
+    def get_all_groups_changes(self, from_token, to_token, limit):
+        from_token = int(from_token)
+        has_changed = self._group_updates_stream_cache.has_any_entity_changed(
+            from_token,
+        )
+        if not has_changed:
+            return []
+
+        def _get_all_groups_changes_txn(txn):
+            sql = """
+                SELECT stream_id, group_id, user_id, type, content
+                FROM local_group_updates
+                WHERE ? < stream_id AND stream_id <= ?
+                LIMIT ?
+            """
+            txn.execute(sql, (from_token, to_token, limit,))
+            return [(
+                stream_id,
+                group_id,
+                user_id,
+                gtype,
+                json.loads(content_json),
+            ) for stream_id, group_id, user_id, gtype, content_json in txn]
+        return self.runInteraction(
+            "get_all_groups_changes", _get_all_groups_changes_txn,
+        )
+
+    def get_group_stream_token(self):
+        return self._group_updates_id_gen.get_current_token()
diff --git a/synapse/storage/media_repository.py b/synapse/storage/media_repository.py
index 82bb61b811..a66ff7c1e0 100644
--- a/synapse/storage/media_repository.py
+++ b/synapse/storage/media_repository.py
@@ -12,13 +12,23 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
+from synapse.storage.background_updates import BackgroundUpdateStore
 
-from ._base import SQLBaseStore
 
-
-class MediaRepositoryStore(SQLBaseStore):
+class MediaRepositoryStore(BackgroundUpdateStore):
     """Persistence for attachments and avatars"""
 
+    def __init__(self, db_conn, hs):
+        super(MediaRepositoryStore, self).__init__(db_conn, hs)
+
+        self.register_background_index_update(
+            update_name='local_media_repository_url_idx',
+            index_name='local_media_repository_url_idx',
+            table='local_media_repository',
+            columns=['created_ts'],
+            where_clause='url_cache IS NOT NULL',
+        )
+
     def get_default_thumbnails(self, top_level_type, sub_type):
         return []
 
@@ -62,7 +72,7 @@ class MediaRepositoryStore(SQLBaseStore):
         def get_url_cache_txn(txn):
             # get the most recently cached result (relative to the given ts)
             sql = (
-                "SELECT response_code, etag, expires, og, media_id, download_ts"
+                "SELECT response_code, etag, expires_ts, og, media_id, download_ts"
                 " FROM local_media_repository_url_cache"
                 " WHERE url = ? AND download_ts <= ?"
                 " ORDER BY download_ts DESC LIMIT 1"
@@ -74,7 +84,7 @@ class MediaRepositoryStore(SQLBaseStore):
                 # ...or if we've requested a timestamp older than the oldest
                 # copy in the cache, return the oldest copy (if any)
                 sql = (
-                    "SELECT response_code, etag, expires, og, media_id, download_ts"
+                    "SELECT response_code, etag, expires_ts, og, media_id, download_ts"
                     " FROM local_media_repository_url_cache"
                     " WHERE url = ? AND download_ts > ?"
                     " ORDER BY download_ts ASC LIMIT 1"
@@ -86,14 +96,14 @@ class MediaRepositoryStore(SQLBaseStore):
                 return None
 
             return dict(zip((
-                'response_code', 'etag', 'expires', 'og', 'media_id', 'download_ts'
+                'response_code', 'etag', 'expires_ts', 'og', 'media_id', 'download_ts'
             ), row))
 
         return self.runInteraction(
             "get_url_cache", get_url_cache_txn
         )
 
-    def store_url_cache(self, url, response_code, etag, expires, og, media_id,
+    def store_url_cache(self, url, response_code, etag, expires_ts, og, media_id,
                         download_ts):
         return self._simple_insert(
             "local_media_repository_url_cache",
@@ -101,7 +111,7 @@ class MediaRepositoryStore(SQLBaseStore):
                 "url": url,
                 "response_code": response_code,
                 "etag": etag,
-                "expires": expires,
+                "expires_ts": expires_ts,
                 "og": og,
                 "media_id": media_id,
                 "download_ts": download_ts,
@@ -238,3 +248,70 @@ class MediaRepositoryStore(SQLBaseStore):
                 },
             )
         return self.runInteraction("delete_remote_media", delete_remote_media_txn)
+
+    def get_expired_url_cache(self, now_ts):
+        sql = (
+            "SELECT media_id FROM local_media_repository_url_cache"
+            " WHERE expires_ts < ?"
+            " ORDER BY expires_ts ASC"
+            " LIMIT 500"
+        )
+
+        def _get_expired_url_cache_txn(txn):
+            txn.execute(sql, (now_ts,))
+            return [row[0] for row in txn]
+
+        return self.runInteraction("get_expired_url_cache", _get_expired_url_cache_txn)
+
+    def delete_url_cache(self, media_ids):
+        if len(media_ids) == 0:
+            return
+
+        sql = (
+            "DELETE FROM local_media_repository_url_cache"
+            " WHERE media_id = ?"
+        )
+
+        def _delete_url_cache_txn(txn):
+            txn.executemany(sql, [(media_id,) for media_id in media_ids])
+
+        return self.runInteraction("delete_url_cache", _delete_url_cache_txn)
+
+    def get_url_cache_media_before(self, before_ts):
+        sql = (
+            "SELECT media_id FROM local_media_repository"
+            " WHERE created_ts < ? AND url_cache IS NOT NULL"
+            " ORDER BY created_ts ASC"
+            " LIMIT 500"
+        )
+
+        def _get_url_cache_media_before_txn(txn):
+            txn.execute(sql, (before_ts,))
+            return [row[0] for row in txn]
+
+        return self.runInteraction(
+            "get_url_cache_media_before", _get_url_cache_media_before_txn,
+        )
+
+    def delete_url_cache_media(self, media_ids):
+        if len(media_ids) == 0:
+            return
+
+        def _delete_url_cache_media_txn(txn):
+            sql = (
+                "DELETE FROM local_media_repository"
+                " WHERE media_id = ?"
+            )
+
+            txn.executemany(sql, [(media_id,) for media_id in media_ids])
+
+            sql = (
+                "DELETE FROM local_media_repository_thumbnails"
+                " WHERE media_id = ?"
+            )
+
+            txn.executemany(sql, [(media_id,) for media_id in media_ids])
+
+        return self.runInteraction(
+            "delete_url_cache_media", _delete_url_cache_media_txn,
+        )
diff --git a/synapse/storage/prepare_database.py b/synapse/storage/prepare_database.py
index 72b670b83b..d1691bbac2 100644
--- a/synapse/storage/prepare_database.py
+++ b/synapse/storage/prepare_database.py
@@ -25,7 +25,7 @@ logger = logging.getLogger(__name__)
 
 # Remember to update this number every time a change is made to database
 # schema files, so the users will be informed on server restarts.
-SCHEMA_VERSION = 43
+SCHEMA_VERSION = 46
 
 dir_path = os.path.abspath(os.path.dirname(__file__))
 
@@ -44,6 +44,13 @@ def prepare_database(db_conn, database_engine, config):
 
     If `config` is None then prepare_database will assert that no upgrade is
     necessary, *or* will create a fresh database if the database is empty.
+
+    Args:
+        db_conn:
+        database_engine:
+        config (synapse.config.homeserver.HomeServerConfig|None):
+            application config, or None if we are connecting to an existing
+            database which we expect to be configured already
     """
     try:
         cur = db_conn.cursor()
@@ -64,9 +71,13 @@ def prepare_database(db_conn, database_engine, config):
         else:
             _setup_new_database(cur, database_engine)
 
+        # check if any of our configured dynamic modules want a database
+        if config is not None:
+            _apply_module_schemas(cur, database_engine, config)
+
         cur.close()
         db_conn.commit()
-    except:
+    except Exception:
         db_conn.rollback()
         raise
 
@@ -283,6 +294,65 @@ def _upgrade_existing_database(cur, current_version, applied_delta_files,
             )
 
 
+def _apply_module_schemas(txn, database_engine, config):
+    """Apply the module schemas for the dynamic modules, if any
+
+    Args:
+        cur: database cursor
+        database_engine: synapse database engine class
+        config (synapse.config.homeserver.HomeServerConfig):
+            application config
+    """
+    for (mod, _config) in config.password_providers:
+        if not hasattr(mod, 'get_db_schema_files'):
+            continue
+        modname = ".".join((mod.__module__, mod.__name__))
+        _apply_module_schema_files(
+            txn, database_engine, modname, mod.get_db_schema_files(),
+        )
+
+
+def _apply_module_schema_files(cur, database_engine, modname, names_and_streams):
+    """Apply the module schemas for a single module
+
+    Args:
+        cur: database cursor
+        database_engine: synapse database engine class
+        modname (str): fully qualified name of the module
+        names_and_streams (Iterable[(str, file)]): the names and streams of
+            schemas to be applied
+    """
+    cur.execute(
+        database_engine.convert_param_style(
+            "SELECT file FROM applied_module_schemas WHERE module_name = ?"
+        ),
+        (modname,)
+    )
+    applied_deltas = set(d for d, in cur)
+    for (name, stream) in names_and_streams:
+        if name in applied_deltas:
+            continue
+
+        root_name, ext = os.path.splitext(name)
+        if ext != '.sql':
+            raise PrepareDatabaseException(
+                "only .sql files are currently supported for module schemas",
+            )
+
+        logger.info("applying schema %s for %s", name, modname)
+        for statement in get_statements(stream):
+            cur.execute(statement)
+
+        # Mark as done.
+        cur.execute(
+            database_engine.convert_param_style(
+                "INSERT INTO applied_module_schemas (module_name, file)"
+                " VALUES (?,?)",
+            ),
+            (modname, name)
+        )
+
+
 def get_statements(f):
     statement_buffer = ""
     in_comment = False  # If we're in a /* ... */ style comment
diff --git a/synapse/storage/profile.py b/synapse/storage/profile.py
index 26a40905ae..ec02e73bc2 100644
--- a/synapse/storage/profile.py
+++ b/synapse/storage/profile.py
@@ -13,6 +13,11 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+from twisted.internet import defer
+
+from synapse.storage.roommember import ProfileInfo
+from synapse.api.errors import StoreError
+
 from ._base import SQLBaseStore
 
 
@@ -24,6 +29,30 @@ class ProfileStore(SQLBaseStore):
             desc="create_profile",
         )
 
+    @defer.inlineCallbacks
+    def get_profileinfo(self, user_localpart):
+        try:
+            profile = yield self._simple_select_one(
+                table="profiles",
+                keyvalues={"user_id": user_localpart},
+                retcols=("displayname", "avatar_url"),
+                desc="get_profileinfo",
+            )
+        except StoreError as e:
+            if e.code == 404:
+                # no match
+                defer.returnValue(ProfileInfo(None, None))
+                return
+            else:
+                raise
+
+        defer.returnValue(
+            ProfileInfo(
+                avatar_url=profile['avatar_url'],
+                display_name=profile['displayname'],
+            )
+        )
+
     def get_profile_displayname(self, user_localpart):
         return self._simple_select_one_onecol(
             table="profiles",
@@ -55,3 +84,99 @@ class ProfileStore(SQLBaseStore):
             updatevalues={"avatar_url": new_avatar_url},
             desc="set_profile_avatar_url",
         )
+
+    def get_from_remote_profile_cache(self, user_id):
+        return self._simple_select_one(
+            table="remote_profile_cache",
+            keyvalues={"user_id": user_id},
+            retcols=("displayname", "avatar_url",),
+            allow_none=True,
+            desc="get_from_remote_profile_cache",
+        )
+
+    def add_remote_profile_cache(self, user_id, displayname, avatar_url):
+        """Ensure we are caching the remote user's profiles.
+
+        This should only be called when `is_subscribed_remote_profile_for_user`
+        would return true for the user.
+        """
+        return self._simple_upsert(
+            table="remote_profile_cache",
+            keyvalues={"user_id": user_id},
+            values={
+                "displayname": displayname,
+                "avatar_url": avatar_url,
+                "last_check": self._clock.time_msec(),
+            },
+            desc="add_remote_profile_cache",
+        )
+
+    def update_remote_profile_cache(self, user_id, displayname, avatar_url):
+        return self._simple_update(
+            table="remote_profile_cache",
+            keyvalues={"user_id": user_id},
+            values={
+                "displayname": displayname,
+                "avatar_url": avatar_url,
+                "last_check": self._clock.time_msec(),
+            },
+            desc="update_remote_profile_cache",
+        )
+
+    @defer.inlineCallbacks
+    def maybe_delete_remote_profile_cache(self, user_id):
+        """Check if we still care about the remote user's profile, and if we
+        don't then remove their profile from the cache
+        """
+        subscribed = yield self.is_subscribed_remote_profile_for_user(user_id)
+        if not subscribed:
+            yield self._simple_delete(
+                table="remote_profile_cache",
+                keyvalues={"user_id": user_id},
+                desc="delete_remote_profile_cache",
+            )
+
+    def get_remote_profile_cache_entries_that_expire(self, last_checked):
+        """Get all users who haven't been checked since `last_checked`
+        """
+        def _get_remote_profile_cache_entries_that_expire_txn(txn):
+            sql = """
+                SELECT user_id, displayname, avatar_url
+                FROM remote_profile_cache
+                WHERE last_check < ?
+            """
+
+            txn.execute(sql, (last_checked,))
+
+            return self.cursor_to_dict(txn)
+
+        return self.runInteraction(
+            "get_remote_profile_cache_entries_that_expire",
+            _get_remote_profile_cache_entries_that_expire_txn,
+        )
+
+    @defer.inlineCallbacks
+    def is_subscribed_remote_profile_for_user(self, user_id):
+        """Check whether we are interested in a remote user's profile.
+        """
+        res = yield self._simple_select_one_onecol(
+            table="group_users",
+            keyvalues={"user_id": user_id},
+            retcol="user_id",
+            allow_none=True,
+            desc="should_update_remote_profile_cache_for_user",
+        )
+
+        if res:
+            defer.returnValue(True)
+
+        res = yield self._simple_select_one_onecol(
+            table="group_invites",
+            keyvalues={"user_id": user_id},
+            retcol="user_id",
+            allow_none=True,
+            desc="should_update_remote_profile_cache_for_user",
+        )
+
+        if res:
+            defer.returnValue(True)
diff --git a/synapse/storage/pusher.py b/synapse/storage/pusher.py
index 34d2f82b7f..3d8b4d5d5b 100644
--- a/synapse/storage/pusher.py
+++ b/synapse/storage/pusher.py
@@ -204,34 +204,35 @@ class PusherStore(SQLBaseStore):
                    pushkey, pushkey_ts, lang, data, last_stream_ordering,
                    profile_tag=""):
         with self._pushers_id_gen.get_next() as stream_id:
-            def f(txn):
-                newly_inserted = self._simple_upsert_txn(
-                    txn,
-                    "pushers",
-                    {
-                        "app_id": app_id,
-                        "pushkey": pushkey,
-                        "user_name": user_id,
-                    },
-                    {
-                        "access_token": access_token,
-                        "kind": kind,
-                        "app_display_name": app_display_name,
-                        "device_display_name": device_display_name,
-                        "ts": pushkey_ts,
-                        "lang": lang,
-                        "data": encode_canonical_json(data),
-                        "last_stream_ordering": last_stream_ordering,
-                        "profile_tag": profile_tag,
-                        "id": stream_id,
-                    },
-                )
-                if newly_inserted:
-                    # get_if_user_has_pusher only cares if the user has
-                    # at least *one* pusher.
-                    txn.call_after(self.get_if_user_has_pusher.invalidate, (user_id,))
+            # no need to lock because `pushers` has a unique key on
+            # (app_id, pushkey, user_name) so _simple_upsert will retry
+            newly_inserted = yield self._simple_upsert(
+                table="pushers",
+                keyvalues={
+                    "app_id": app_id,
+                    "pushkey": pushkey,
+                    "user_name": user_id,
+                },
+                values={
+                    "access_token": access_token,
+                    "kind": kind,
+                    "app_display_name": app_display_name,
+                    "device_display_name": device_display_name,
+                    "ts": pushkey_ts,
+                    "lang": lang,
+                    "data": encode_canonical_json(data),
+                    "last_stream_ordering": last_stream_ordering,
+                    "profile_tag": profile_tag,
+                    "id": stream_id,
+                },
+                desc="add_pusher",
+                lock=False,
+            )
 
-            yield self.runInteraction("add_pusher", f)
+            if newly_inserted:
+                # get_if_user_has_pusher only cares if the user has
+                # at least *one* pusher.
+                self.get_if_user_has_pusher.invalidate(user_id,)
 
     @defer.inlineCallbacks
     def delete_pusher_by_app_id_pushkey_user_id(self, app_id, pushkey, user_id):
@@ -243,11 +244,19 @@ class PusherStore(SQLBaseStore):
                 "pushers",
                 {"app_id": app_id, "pushkey": pushkey, "user_name": user_id}
             )
-            self._simple_upsert_txn(
+
+            # it's possible for us to end up with duplicate rows for
+            # (app_id, pushkey, user_id) at different stream_ids, but that
+            # doesn't really matter.
+            self._simple_insert_txn(
                 txn,
-                "deleted_pushers",
-                {"app_id": app_id, "pushkey": pushkey, "user_id": user_id},
-                {"stream_id": stream_id},
+                table="deleted_pushers",
+                values={
+                    "stream_id": stream_id,
+                    "app_id": app_id,
+                    "pushkey": pushkey,
+                    "user_id": user_id,
+                },
             )
 
         with self._pushers_id_gen.get_next() as stream_id:
@@ -310,9 +319,12 @@ class PusherStore(SQLBaseStore):
 
     @defer.inlineCallbacks
     def set_throttle_params(self, pusher_id, room_id, params):
+        # no need to lock because `pusher_throttle` has a primary key on
+        # (pusher, room_id) so _simple_upsert will retry
         yield self._simple_upsert(
             "pusher_throttle",
             {"pusher": pusher_id, "room_id": room_id},
             params,
-            desc="set_throttle_params"
+            desc="set_throttle_params",
+            lock=False,
         )
diff --git a/synapse/storage/receipts.py b/synapse/storage/receipts.py
index f42b8014c7..12b3cc7f5f 100644
--- a/synapse/storage/receipts.py
+++ b/synapse/storage/receipts.py
@@ -27,8 +27,8 @@ logger = logging.getLogger(__name__)
 
 
 class ReceiptsStore(SQLBaseStore):
-    def __init__(self, hs):
-        super(ReceiptsStore, self).__init__(hs)
+    def __init__(self, db_conn, hs):
+        super(ReceiptsStore, self).__init__(db_conn, hs)
 
         self._receipts_stream_cache = StreamChangeCache(
             "ReceiptsRoomChangeCache", self._receipts_id_gen.get_current_token()
diff --git a/synapse/storage/registration.py b/synapse/storage/registration.py
index 20acd58fcf..3aa810981f 100644
--- a/synapse/storage/registration.py
+++ b/synapse/storage/registration.py
@@ -24,8 +24,8 @@ from synapse.util.caches.descriptors import cached, cachedInlineCallbacks
 
 class RegistrationStore(background_updates.BackgroundUpdateStore):
 
-    def __init__(self, hs):
-        super(RegistrationStore, self).__init__(hs)
+    def __init__(self, db_conn, hs):
+        super(RegistrationStore, self).__init__(db_conn, hs)
 
         self.clock = hs.get_clock()
 
@@ -36,12 +36,15 @@ class RegistrationStore(background_updates.BackgroundUpdateStore):
             columns=["user_id", "device_id"],
         )
 
-        self.register_background_index_update(
-            "refresh_tokens_device_index",
-            index_name="refresh_tokens_device_id",
-            table="refresh_tokens",
-            columns=["user_id", "device_id"],
-        )
+        # we no longer use refresh tokens, but it's possible that some people
+        # might have a background update queued to build this index. Just
+        # clear the background update.
+        @defer.inlineCallbacks
+        def noop_update(progress, batch_size):
+            yield self._end_background_update("refresh_tokens_device_index")
+            defer.returnValue(1)
+        self.register_background_update_handler(
+            "refresh_tokens_device_index", noop_update)
 
     @defer.inlineCallbacks
     def add_access_token_to_user(self, user_id, token, device_id=None):
@@ -177,9 +180,11 @@ class RegistrationStore(background_updates.BackgroundUpdateStore):
             )
 
         if create_profile_with_localpart:
+            # set a default displayname serverside to avoid ugly race
+            # between auto-joins and clients trying to set displaynames
             txn.execute(
-                "INSERT INTO profiles(user_id) VALUES (?)",
-                (create_profile_with_localpart,)
+                "INSERT INTO profiles(user_id, displayname) VALUES (?,?)",
+                (create_profile_with_localpart, create_profile_with_localpart)
             )
 
         self._invalidate_cache_and_stream(
@@ -236,12 +241,10 @@ class RegistrationStore(background_updates.BackgroundUpdateStore):
             "user_set_password_hash", user_set_password_hash_txn
         )
 
-    @defer.inlineCallbacks
     def user_delete_access_tokens(self, user_id, except_token_id=None,
-                                  device_id=None,
-                                  delete_refresh_tokens=False):
+                                  device_id=None):
         """
-        Invalidate access/refresh tokens belonging to a user
+        Invalidate access tokens belonging to a user
 
         Args:
             user_id (str):  ID of user the tokens belong to
@@ -250,10 +253,9 @@ class RegistrationStore(background_updates.BackgroundUpdateStore):
             device_id (str|None):  ID of device the tokens are associated with.
                 If None, tokens associated with any device (or no device) will
                 be deleted
-            delete_refresh_tokens (bool):  True to delete refresh tokens as
-                well as access tokens.
         Returns:
-            defer.Deferred:
+            defer.Deferred[list[str, int, str|None, int]]: a list of
+                (token, token id, device id) for each of the deleted tokens
         """
         def f(txn):
             keyvalues = {
@@ -262,13 +264,6 @@ class RegistrationStore(background_updates.BackgroundUpdateStore):
             if device_id is not None:
                 keyvalues["device_id"] = device_id
 
-            if delete_refresh_tokens:
-                self._simple_delete_txn(
-                    txn,
-                    table="refresh_tokens",
-                    keyvalues=keyvalues,
-                )
-
             items = keyvalues.items()
             where_clause = " AND ".join(k + " = ?" for k, _ in items)
             values = [v for _, v in items]
@@ -277,14 +272,14 @@ class RegistrationStore(background_updates.BackgroundUpdateStore):
                 values.append(except_token_id)
 
             txn.execute(
-                "SELECT token FROM access_tokens WHERE %s" % where_clause,
+                "SELECT token, id, device_id FROM access_tokens WHERE %s" % where_clause,
                 values
             )
-            rows = self.cursor_to_dict(txn)
+            tokens_and_devices = [(r[0], r[1], r[2]) for r in txn]
 
-            for row in rows:
+            for token, _, _ in tokens_and_devices:
                 self._invalidate_cache_and_stream(
-                    txn, self.get_user_by_access_token, (row["token"],)
+                    txn, self.get_user_by_access_token, (token,)
                 )
 
             txn.execute(
@@ -292,7 +287,9 @@ class RegistrationStore(background_updates.BackgroundUpdateStore):
                 values
             )
 
-        yield self.runInteraction(
+            return tokens_and_devices
+
+        return self.runInteraction(
             "user_delete_access_tokens", f,
         )
 
diff --git a/synapse/storage/roommember.py b/synapse/storage/roommember.py
index 457ca288d0..3e77fd3901 100644
--- a/synapse/storage/roommember.py
+++ b/synapse/storage/roommember.py
@@ -49,8 +49,8 @@ _MEMBERSHIP_PROFILE_UPDATE_NAME = "room_membership_profile_update"
 
 
 class RoomMemberStore(SQLBaseStore):
-    def __init__(self, hs):
-        super(RoomMemberStore, self).__init__(hs)
+    def __init__(self, db_conn, hs):
+        super(RoomMemberStore, self).__init__(db_conn, hs)
         self.register_background_update_handler(
             _MEMBERSHIP_PROFILE_UPDATE_NAME, self._background_add_membership_profile
         )
@@ -533,6 +533,46 @@ class RoomMemberStore(SQLBaseStore):
 
         defer.returnValue(True)
 
+    @cachedInlineCallbacks()
+    def was_host_joined(self, room_id, host):
+        """Check whether the server is or ever was in the room.
+
+        Args:
+            room_id (str)
+            host (str)
+
+        Returns:
+            Deferred: Resolves to True if the host is/was in the room, otherwise
+            False.
+        """
+        if '%' in host or '_' in host:
+            raise Exception("Invalid host name")
+
+        sql = """
+            SELECT user_id FROM room_memberships
+            WHERE room_id = ?
+                AND user_id LIKE ?
+                AND membership = 'join'
+            LIMIT 1
+        """
+
+        # We do need to be careful to ensure that host doesn't have any wild cards
+        # in it, but we checked above for known ones and we'll check below that
+        # the returned user actually has the correct domain.
+        like_clause = "%:" + host
+
+        rows = yield self._execute("was_host_joined", None, sql, room_id, like_clause)
+
+        if not rows:
+            defer.returnValue(False)
+
+        user_id = rows[0][0]
+        if get_domain_from_id(user_id) != host:
+            # This can only happen if the host name has something funky in it
+            raise Exception("Invalid host name")
+
+        defer.returnValue(True)
+
     def get_joined_hosts(self, room_id, state_entry):
         state_group = state_entry.state_group
         if not state_group:
@@ -596,7 +636,7 @@ class RoomMemberStore(SQLBaseStore):
                 room_id = row["room_id"]
                 try:
                     content = json.loads(row["content"])
-                except:
+                except Exception:
                     continue
 
                 display_name = content.get("displayname", None)
diff --git a/synapse/storage/schema/delta/30/as_users.py b/synapse/storage/schema/delta/30/as_users.py
index 5b7d8d1ab5..c53e53c94f 100644
--- a/synapse/storage/schema/delta/30/as_users.py
+++ b/synapse/storage/schema/delta/30/as_users.py
@@ -22,7 +22,7 @@ def run_create(cur, database_engine, *args, **kwargs):
     # NULL indicates user was not registered by an appservice.
     try:
         cur.execute("ALTER TABLE users ADD COLUMN appservice_id TEXT")
-    except:
+    except Exception:
         # Maybe we already added the column? Hope so...
         pass
 
diff --git a/synapse/storage/schema/delta/43/user_share.sql b/synapse/storage/schema/delta/43/user_share.sql
index 4501d90cbb..ee7062abe4 100644
--- a/synapse/storage/schema/delta/43/user_share.sql
+++ b/synapse/storage/schema/delta/43/user_share.sql
@@ -29,5 +29,5 @@ CREATE INDEX users_who_share_rooms_r_idx ON users_who_share_rooms(room_id);
 CREATE INDEX users_who_share_rooms_o_idx ON users_who_share_rooms(other_user_id);
 
 
--- Make sure that we popualte the table initially
+-- Make sure that we populate the table initially
 UPDATE user_directory_stream_pos SET stream_id = NULL;
diff --git a/synapse/storage/schema/delta/44/expire_url_cache.sql b/synapse/storage/schema/delta/44/expire_url_cache.sql
new file mode 100644
index 0000000000..b12f9b2ebf
--- /dev/null
+++ b/synapse/storage/schema/delta/44/expire_url_cache.sql
@@ -0,0 +1,41 @@
+/* Copyright 2017 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- this didn't work on SQLite 3.7 (because of lack of partial indexes), so was
+-- removed and replaced with 46/local_media_repository_url_idx.sql.
+--
+-- CREATE INDEX local_media_repository_url_idx ON local_media_repository(created_ts) WHERE url_cache IS NOT NULL;
+
+-- we need to change `expires` to `expires_ts` so that we can index on it. SQLite doesn't support
+-- indices on expressions until 3.9.
+CREATE TABLE local_media_repository_url_cache_new(
+    url TEXT,
+    response_code INTEGER,
+    etag TEXT,
+    expires_ts BIGINT,
+    og TEXT,
+    media_id TEXT,
+    download_ts BIGINT
+);
+
+INSERT INTO local_media_repository_url_cache_new
+    SELECT url, response_code, etag, expires + download_ts, og, media_id, download_ts FROM local_media_repository_url_cache;
+
+DROP TABLE local_media_repository_url_cache;
+ALTER TABLE local_media_repository_url_cache_new RENAME TO local_media_repository_url_cache;
+
+CREATE INDEX local_media_repository_url_cache_expires_idx ON local_media_repository_url_cache(expires_ts);
+CREATE INDEX local_media_repository_url_cache_by_url_download_ts ON local_media_repository_url_cache(url, download_ts);
+CREATE INDEX local_media_repository_url_cache_media_idx ON local_media_repository_url_cache(media_id);
diff --git a/synapse/storage/schema/delta/45/group_server.sql b/synapse/storage/schema/delta/45/group_server.sql
new file mode 100644
index 0000000000..b2333848a0
--- /dev/null
+++ b/synapse/storage/schema/delta/45/group_server.sql
@@ -0,0 +1,167 @@
+/* Copyright 2017 Vector Creations Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+CREATE TABLE groups (
+    group_id TEXT NOT NULL,
+    name TEXT,  -- the display name of the room
+    avatar_url TEXT,
+    short_description TEXT,
+    long_description TEXT
+);
+
+CREATE UNIQUE INDEX groups_idx ON groups(group_id);
+
+
+-- list of users the group server thinks are joined
+CREATE TABLE group_users (
+    group_id TEXT NOT NULL,
+    user_id TEXT NOT NULL,
+    is_admin BOOLEAN NOT NULL,
+    is_public BOOLEAN NOT NULL  -- whether the users membership can be seen by everyone
+);
+
+
+CREATE INDEX groups_users_g_idx ON group_users(group_id, user_id);
+CREATE INDEX groups_users_u_idx ON group_users(user_id);
+
+-- list of users the group server thinks are invited
+CREATE TABLE group_invites (
+    group_id TEXT NOT NULL,
+    user_id TEXT NOT NULL
+);
+
+CREATE INDEX groups_invites_g_idx ON group_invites(group_id, user_id);
+CREATE INDEX groups_invites_u_idx ON group_invites(user_id);
+
+
+CREATE TABLE group_rooms (
+    group_id TEXT NOT NULL,
+    room_id TEXT NOT NULL,
+    is_public BOOLEAN NOT NULL  -- whether the room can be seen by everyone
+);
+
+CREATE UNIQUE INDEX groups_rooms_g_idx ON group_rooms(group_id, room_id);
+CREATE INDEX groups_rooms_r_idx ON group_rooms(room_id);
+
+
+-- Rooms to include in the summary
+CREATE TABLE group_summary_rooms (
+    group_id TEXT NOT NULL,
+    room_id TEXT NOT NULL,
+    category_id TEXT NOT NULL,
+    room_order BIGINT NOT NULL,
+    is_public BOOLEAN NOT NULL, -- whether the room should be show to everyone
+    UNIQUE (group_id, category_id, room_id, room_order),
+    CHECK (room_order > 0)
+);
+
+CREATE UNIQUE INDEX group_summary_rooms_g_idx ON group_summary_rooms(group_id, room_id, category_id);
+
+
+-- Categories to include in the summary
+CREATE TABLE group_summary_room_categories (
+    group_id TEXT NOT NULL,
+    category_id TEXT NOT NULL,
+    cat_order BIGINT NOT NULL,
+    UNIQUE (group_id, category_id, cat_order),
+    CHECK (cat_order > 0)
+);
+
+-- The categories in the group
+CREATE TABLE group_room_categories (
+    group_id TEXT NOT NULL,
+    category_id TEXT NOT NULL,
+    profile TEXT NOT NULL,
+    is_public BOOLEAN NOT NULL, -- whether the category should be show to everyone
+    UNIQUE (group_id, category_id)
+);
+
+-- The users to include in the group summary
+CREATE TABLE group_summary_users (
+    group_id TEXT NOT NULL,
+    user_id TEXT NOT NULL,
+    role_id TEXT NOT NULL,
+    user_order BIGINT NOT NULL,
+    is_public BOOLEAN NOT NULL  -- whether the user should be show to everyone
+);
+
+CREATE INDEX group_summary_users_g_idx ON group_summary_users(group_id);
+
+-- The roles to include in the group summary
+CREATE TABLE group_summary_roles (
+    group_id TEXT NOT NULL,
+    role_id TEXT NOT NULL,
+    role_order BIGINT NOT NULL,
+    UNIQUE (group_id, role_id, role_order),
+    CHECK (role_order > 0)
+);
+
+
+-- The roles in a groups
+CREATE TABLE group_roles (
+    group_id TEXT NOT NULL,
+    role_id TEXT NOT NULL,
+    profile TEXT NOT NULL,
+    is_public BOOLEAN NOT NULL,  -- whether the role should be show to everyone
+    UNIQUE (group_id, role_id)
+);
+
+
+-- List of  attestations we've given out and need to renew
+CREATE TABLE group_attestations_renewals (
+    group_id TEXT NOT NULL,
+    user_id TEXT NOT NULL,
+    valid_until_ms BIGINT NOT NULL
+);
+
+CREATE INDEX group_attestations_renewals_g_idx ON group_attestations_renewals(group_id, user_id);
+CREATE INDEX group_attestations_renewals_u_idx ON group_attestations_renewals(user_id);
+CREATE INDEX group_attestations_renewals_v_idx ON group_attestations_renewals(valid_until_ms);
+
+
+-- List of attestations we've received from remotes and are interested in.
+CREATE TABLE group_attestations_remote (
+    group_id TEXT NOT NULL,
+    user_id TEXT NOT NULL,
+    valid_until_ms BIGINT NOT NULL,
+    attestation_json TEXT NOT NULL
+);
+
+CREATE INDEX group_attestations_remote_g_idx ON group_attestations_remote(group_id, user_id);
+CREATE INDEX group_attestations_remote_u_idx ON group_attestations_remote(user_id);
+CREATE INDEX group_attestations_remote_v_idx ON group_attestations_remote(valid_until_ms);
+
+
+-- The group membership for the HS's users
+CREATE TABLE local_group_membership (
+    group_id TEXT NOT NULL,
+    user_id TEXT NOT NULL,
+    is_admin BOOLEAN NOT NULL,
+    membership TEXT NOT NULL,
+    is_publicised BOOLEAN NOT NULL,  -- if the user is publicising their membership
+    content TEXT NOT NULL
+);
+
+CREATE INDEX local_group_membership_u_idx ON local_group_membership(user_id, group_id);
+CREATE INDEX local_group_membership_g_idx ON local_group_membership(group_id);
+
+
+CREATE TABLE local_group_updates (
+    stream_id BIGINT NOT NULL,
+    group_id TEXT NOT NULL,
+    user_id TEXT NOT NULL,
+    type TEXT NOT NULL,
+    content TEXT NOT NULL
+);
diff --git a/synapse/storage/schema/delta/23/refresh_tokens.sql b/synapse/storage/schema/delta/45/profile_cache.sql
index 34db0cf12b..e5ddc84df0 100644
--- a/synapse/storage/schema/delta/23/refresh_tokens.sql
+++ b/synapse/storage/schema/delta/45/profile_cache.sql
@@ -1,4 +1,4 @@
-/* Copyright 2015, 2016 OpenMarket Ltd
+/* Copyright 2017 New Vector Ltd
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -13,9 +13,16 @@
  * limitations under the License.
  */
 
-CREATE TABLE IF NOT EXISTS refresh_tokens(
-    id INTEGER PRIMARY KEY,
-    token TEXT NOT NULL,
+
+-- A subset of remote users whose profiles we have cached.
+-- Whether a user is in this table or not is defined by the storage function
+-- `is_subscribed_remote_profile_for_user`
+CREATE TABLE remote_profile_cache (
     user_id TEXT NOT NULL,
-    UNIQUE (token)
+    displayname TEXT,
+    avatar_url TEXT,
+    last_check BIGINT NOT NULL
 );
+
+CREATE UNIQUE INDEX remote_profile_cache_user_id ON remote_profile_cache(user_id);
+CREATE INDEX remote_profile_cache_time ON remote_profile_cache(last_check);
diff --git a/synapse/storage/schema/delta/33/refreshtoken_device.sql b/synapse/storage/schema/delta/46/drop_refresh_tokens.sql
index 290bd6da86..68c48a89a9 100644
--- a/synapse/storage/schema/delta/33/refreshtoken_device.sql
+++ b/synapse/storage/schema/delta/46/drop_refresh_tokens.sql
@@ -1,4 +1,4 @@
-/* Copyright 2016 OpenMarket Ltd
+/* Copyright 2017 New Vector Ltd
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -13,4 +13,5 @@
  * limitations under the License.
  */
 
-ALTER TABLE refresh_tokens ADD COLUMN device_id TEXT;
+/* we no longer use (or create) the refresh_tokens table */
+DROP TABLE IF EXISTS refresh_tokens;
diff --git a/synapse/storage/schema/delta/46/drop_unique_deleted_pushers.sql b/synapse/storage/schema/delta/46/drop_unique_deleted_pushers.sql
new file mode 100644
index 0000000000..bb307889c1
--- /dev/null
+++ b/synapse/storage/schema/delta/46/drop_unique_deleted_pushers.sql
@@ -0,0 +1,35 @@
+/* Copyright 2017 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- drop the unique constraint on deleted_pushers so that we can just insert
+-- into it rather than upserting.
+
+CREATE TABLE deleted_pushers2 (
+    stream_id BIGINT NOT NULL,
+    app_id TEXT NOT NULL,
+    pushkey TEXT NOT NULL,
+    user_id TEXT NOT NULL
+);
+
+INSERT INTO deleted_pushers2 (stream_id, app_id, pushkey, user_id)
+    SELECT stream_id, app_id, pushkey, user_id from deleted_pushers;
+
+DROP TABLE deleted_pushers;
+ALTER TABLE deleted_pushers2 RENAME TO deleted_pushers;
+
+-- create the index after doing the inserts because that's more efficient.
+-- it also means we can give it the same name as the old one without renaming.
+CREATE INDEX deleted_pushers_stream_id ON deleted_pushers (stream_id);
+
diff --git a/synapse/storage/schema/delta/46/group_server.sql b/synapse/storage/schema/delta/46/group_server.sql
new file mode 100644
index 0000000000..097679bc9a
--- /dev/null
+++ b/synapse/storage/schema/delta/46/group_server.sql
@@ -0,0 +1,32 @@
+/* Copyright 2017 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+CREATE TABLE groups_new (
+    group_id TEXT NOT NULL,
+    name TEXT,  -- the display name of the room
+    avatar_url TEXT,
+    short_description TEXT,
+    long_description TEXT,
+    is_public BOOL NOT NULL -- whether non-members can access group APIs
+);
+
+-- NB: awful hack to get the default to be true on postgres and 1 on sqlite
+INSERT INTO groups_new
+    SELECT group_id, name, avatar_url, short_description, long_description, (1=1) FROM groups;
+
+DROP TABLE groups;
+ALTER TABLE groups_new RENAME TO groups;
+
+CREATE UNIQUE INDEX groups_idx ON groups(group_id);
diff --git a/synapse/storage/schema/delta/33/refreshtoken_device_index.sql b/synapse/storage/schema/delta/46/local_media_repository_url_idx.sql
index bb225dafbf..bbfc7f5d1a 100644
--- a/synapse/storage/schema/delta/33/refreshtoken_device_index.sql
+++ b/synapse/storage/schema/delta/46/local_media_repository_url_idx.sql
@@ -1,4 +1,4 @@
-/* Copyright 2016 OpenMarket Ltd
+/* Copyright 2017 New Vector Ltd
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -13,5 +13,12 @@
  * limitations under the License.
  */
 
+-- register a background update which will recreate the
+-- local_media_repository_url_idx index.
+--
+-- We do this as a bg update not because it is a particularly onerous
+-- operation, but because we'd like it to be a partial index if possible, and
+-- the background_index_update code will understand whether we are on
+-- postgres or sqlite and behave accordingly.
 INSERT INTO background_updates (update_name, progress_json) VALUES
-  ('refresh_tokens_device_index', '{}');
+    ('local_media_repository_url_idx', '{}');
diff --git a/synapse/storage/schema/delta/46/user_dir_null_room_ids.sql b/synapse/storage/schema/delta/46/user_dir_null_room_ids.sql
new file mode 100644
index 0000000000..cb0d5a2576
--- /dev/null
+++ b/synapse/storage/schema/delta/46/user_dir_null_room_ids.sql
@@ -0,0 +1,35 @@
+/* Copyright 2017 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- change the user_directory table to also cover global local user profiles
+-- rather than just profiles within specific rooms.
+
+CREATE TABLE user_directory2 (
+    user_id TEXT NOT NULL,
+    room_id TEXT,
+    display_name TEXT,
+    avatar_url TEXT
+);
+
+INSERT INTO user_directory2(user_id, room_id, display_name, avatar_url)
+    SELECT user_id, room_id, display_name, avatar_url from user_directory;
+
+DROP TABLE user_directory;
+ALTER TABLE user_directory2 RENAME TO user_directory;
+
+-- create indexes after doing the inserts because that's more efficient.
+-- it also means we can give it the same name as the old one without renaming.
+CREATE INDEX user_directory_room_idx ON user_directory(room_id);
+CREATE UNIQUE INDEX user_directory_user_idx ON user_directory(user_id);
diff --git a/synapse/storage/schema/delta/46/user_dir_typos.sql b/synapse/storage/schema/delta/46/user_dir_typos.sql
new file mode 100644
index 0000000000..d9505f8da1
--- /dev/null
+++ b/synapse/storage/schema/delta/46/user_dir_typos.sql
@@ -0,0 +1,24 @@
+/* Copyright 2017 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- this is just embarassing :|
+ALTER TABLE users_in_pubic_room RENAME TO users_in_public_rooms;
+
+-- this is only 300K rows on matrix.org and takes ~3s to generate the index,
+-- so is hopefully not going to block anyone else for that long...
+CREATE INDEX users_in_public_rooms_room_idx ON users_in_public_rooms(room_id);
+CREATE UNIQUE INDEX users_in_public_rooms_user_idx ON users_in_public_rooms(user_id);
+DROP INDEX users_in_pubic_room_room_idx;
+DROP INDEX users_in_pubic_room_user_idx;
diff --git a/synapse/storage/schema/schema_version.sql b/synapse/storage/schema/schema_version.sql
index a7ade69986..42e5cb6df5 100644
--- a/synapse/storage/schema/schema_version.sql
+++ b/synapse/storage/schema/schema_version.sql
@@ -25,3 +25,10 @@ CREATE TABLE IF NOT EXISTS applied_schema_deltas(
     file TEXT NOT NULL,
     UNIQUE(version, file)
 );
+
+-- a list of schema files we have loaded on behalf of dynamic modules
+CREATE TABLE IF NOT EXISTS applied_module_schemas(
+    module_name TEXT NOT NULL,
+    file TEXT NOT NULL,
+    UNIQUE(module_name, file)
+);
diff --git a/synapse/storage/search.py b/synapse/storage/search.py
index 8f2b3c4435..479b04c636 100644
--- a/synapse/storage/search.py
+++ b/synapse/storage/search.py
@@ -33,8 +33,8 @@ class SearchStore(BackgroundUpdateStore):
     EVENT_SEARCH_ORDER_UPDATE_NAME = "event_search_order"
     EVENT_SEARCH_USE_GIST_POSTGRES_NAME = "event_search_postgres_gist"
 
-    def __init__(self, hs):
-        super(SearchStore, self).__init__(hs)
+    def __init__(self, db_conn, hs):
+        super(SearchStore, self).__init__(db_conn, hs)
         self.register_background_update_handler(
             self.EVENT_SEARCH_UPDATE_NAME, self._background_reindex_search
         )
@@ -81,7 +81,7 @@ class SearchStore(BackgroundUpdateStore):
                     etype = row["type"]
                     try:
                         content = json.loads(row["content"])
-                    except:
+                    except Exception:
                         continue
 
                     if etype == "m.room.message":
@@ -407,7 +407,7 @@ class SearchStore(BackgroundUpdateStore):
                 origin_server_ts, stream = pagination_token.split(",")
                 origin_server_ts = int(origin_server_ts)
                 stream = int(stream)
-            except:
+            except Exception:
                 raise SynapseError(400, "Invalid pagination token")
 
             clauses.append(
diff --git a/synapse/storage/state.py b/synapse/storage/state.py
index 5673e4aa96..360e3e4355 100644
--- a/synapse/storage/state.py
+++ b/synapse/storage/state.py
@@ -13,16 +13,18 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-from ._base import SQLBaseStore
-from synapse.util.caches.descriptors import cached, cachedList
-from synapse.util.caches import intern_string
-from synapse.util.stringutils import to_ascii
-from synapse.storage.engines import PostgresEngine
+from collections import namedtuple
+import logging
 
 from twisted.internet import defer
-from collections import namedtuple
 
-import logging
+from synapse.storage.background_updates import BackgroundUpdateStore
+from synapse.storage.engines import PostgresEngine
+from synapse.util.caches import intern_string, CACHE_SIZE_FACTOR
+from synapse.util.caches.descriptors import cached, cachedList
+from synapse.util.caches.dictionary_cache import DictionaryCache
+from synapse.util.stringutils import to_ascii
+from ._base import SQLBaseStore
 
 logger = logging.getLogger(__name__)
 
@@ -40,45 +42,22 @@ class _GetStateGroupDelta(namedtuple("_GetStateGroupDelta", ("prev_group", "delt
         return len(self.delta_ids) if self.delta_ids else 0
 
 
-class StateStore(SQLBaseStore):
-    """ Keeps track of the state at a given event.
+class StateGroupReadStore(SQLBaseStore):
+    """The read-only parts of StateGroupStore
 
-    This is done by the concept of `state groups`. Every event is a assigned
-    a state group (identified by an arbitrary string), which references a
-    collection of state events. The current state of an event is then the
-    collection of state events referenced by the event's state group.
-
-    Hence, every change in the current state causes a new state group to be
-    generated. However, if no change happens (e.g., if we get a message event
-    with only one parent it inherits the state group from its parent.)
-
-    There are three tables:
-      * `state_groups`: Stores group name, first event with in the group and
-        room id.
-      * `event_to_state_groups`: Maps events to state groups.
-      * `state_groups_state`: Maps state group to state events.
+    None of these functions write to the state tables, so are suitable for
+    including in the SlavedStores.
     """
 
     STATE_GROUP_DEDUPLICATION_UPDATE_NAME = "state_group_state_deduplication"
     STATE_GROUP_INDEX_UPDATE_NAME = "state_group_state_type_index"
     CURRENT_STATE_INDEX_UPDATE_NAME = "current_state_members_idx"
 
-    def __init__(self, hs):
-        super(StateStore, self).__init__(hs)
-        self.register_background_update_handler(
-            self.STATE_GROUP_DEDUPLICATION_UPDATE_NAME,
-            self._background_deduplicate_state,
-        )
-        self.register_background_update_handler(
-            self.STATE_GROUP_INDEX_UPDATE_NAME,
-            self._background_index_state,
-        )
-        self.register_background_index_update(
-            self.CURRENT_STATE_INDEX_UPDATE_NAME,
-            index_name="current_state_events_member_index",
-            table="current_state_events",
-            columns=["state_key"],
-            where_clause="type='m.room.member'",
+    def __init__(self, db_conn, hs):
+        super(StateGroupReadStore, self).__init__(db_conn, hs)
+
+        self._state_group_cache = DictionaryCache(
+            "*stateGroupCache*", 100000 * CACHE_SIZE_FACTOR
         )
 
     @cached(max_entries=100000, iterable=True)
@@ -190,178 +169,6 @@ class StateStore(SQLBaseStore):
             for group, event_id_map in group_to_ids.iteritems()
         })
 
-    def _have_persisted_state_group_txn(self, txn, state_group):
-        txn.execute(
-            "SELECT count(*) FROM state_groups WHERE id = ?",
-            (state_group,)
-        )
-        row = txn.fetchone()
-        return row and row[0]
-
-    def _store_mult_state_groups_txn(self, txn, events_and_contexts):
-        state_groups = {}
-        for event, context in events_and_contexts:
-            if event.internal_metadata.is_outlier():
-                continue
-
-            if context.current_state_ids is None:
-                # AFAIK, this can never happen
-                logger.error(
-                    "Non-outlier event %s had current_state_ids==None",
-                    event.event_id)
-                continue
-
-            # if the event was rejected, just give it the same state as its
-            # predecessor.
-            if context.rejected:
-                state_groups[event.event_id] = context.prev_group
-                continue
-
-            state_groups[event.event_id] = context.state_group
-
-            if self._have_persisted_state_group_txn(txn, context.state_group):
-                continue
-
-            self._simple_insert_txn(
-                txn,
-                table="state_groups",
-                values={
-                    "id": context.state_group,
-                    "room_id": event.room_id,
-                    "event_id": event.event_id,
-                },
-            )
-
-            # We persist as a delta if we can, while also ensuring the chain
-            # of deltas isn't tooo long, as otherwise read performance degrades.
-            if context.prev_group:
-                is_in_db = self._simple_select_one_onecol_txn(
-                    txn,
-                    table="state_groups",
-                    keyvalues={"id": context.prev_group},
-                    retcol="id",
-                    allow_none=True,
-                )
-                if not is_in_db:
-                    raise Exception(
-                        "Trying to persist state with unpersisted prev_group: %r"
-                        % (context.prev_group,)
-                    )
-
-                potential_hops = self._count_state_group_hops_txn(
-                    txn, context.prev_group
-                )
-            if context.prev_group and potential_hops < MAX_STATE_DELTA_HOPS:
-                self._simple_insert_txn(
-                    txn,
-                    table="state_group_edges",
-                    values={
-                        "state_group": context.state_group,
-                        "prev_state_group": context.prev_group,
-                    },
-                )
-
-                self._simple_insert_many_txn(
-                    txn,
-                    table="state_groups_state",
-                    values=[
-                        {
-                            "state_group": context.state_group,
-                            "room_id": event.room_id,
-                            "type": key[0],
-                            "state_key": key[1],
-                            "event_id": state_id,
-                        }
-                        for key, state_id in context.delta_ids.iteritems()
-                    ],
-                )
-            else:
-                self._simple_insert_many_txn(
-                    txn,
-                    table="state_groups_state",
-                    values=[
-                        {
-                            "state_group": context.state_group,
-                            "room_id": event.room_id,
-                            "type": key[0],
-                            "state_key": key[1],
-                            "event_id": state_id,
-                        }
-                        for key, state_id in context.current_state_ids.iteritems()
-                    ],
-                )
-
-            # Prefill the state group cache with this group.
-            # It's fine to use the sequence like this as the state group map
-            # is immutable. (If the map wasn't immutable then this prefill could
-            # race with another update)
-            txn.call_after(
-                self._state_group_cache.update,
-                self._state_group_cache.sequence,
-                key=context.state_group,
-                value=dict(context.current_state_ids),
-                full=True,
-            )
-
-        self._simple_insert_many_txn(
-            txn,
-            table="event_to_state_groups",
-            values=[
-                {
-                    "state_group": state_group_id,
-                    "event_id": event_id,
-                }
-                for event_id, state_group_id in state_groups.iteritems()
-            ],
-        )
-
-        for event_id, state_group_id in state_groups.iteritems():
-            txn.call_after(
-                self._get_state_group_for_event.prefill,
-                (event_id,), state_group_id
-            )
-
-    def _count_state_group_hops_txn(self, txn, state_group):
-        """Given a state group, count how many hops there are in the tree.
-
-        This is used to ensure the delta chains don't get too long.
-        """
-        if isinstance(self.database_engine, PostgresEngine):
-            sql = ("""
-                WITH RECURSIVE state(state_group) AS (
-                    VALUES(?::bigint)
-                    UNION ALL
-                    SELECT prev_state_group FROM state_group_edges e, state s
-                    WHERE s.state_group = e.state_group
-                )
-                SELECT count(*) FROM state;
-            """)
-
-            txn.execute(sql, (state_group,))
-            row = txn.fetchone()
-            if row and row[0]:
-                return row[0]
-            else:
-                return 0
-        else:
-            # We don't use WITH RECURSIVE on sqlite3 as there are distributions
-            # that ship with an sqlite3 version that doesn't support it (e.g. wheezy)
-            next_group = state_group
-            count = 0
-
-            while next_group:
-                next_group = self._simple_select_one_onecol_txn(
-                    txn,
-                    table="state_group_edges",
-                    keyvalues={"state_group": next_group},
-                    retcol="prev_state_group",
-                    allow_none=True,
-                )
-                if next_group:
-                    count += 1
-
-            return count
-
     @defer.inlineCallbacks
     def _get_state_groups_from_groups(self, groups, types):
         """Returns dictionary state_group -> (dict of (type, state_key) -> event id)
@@ -742,6 +549,220 @@ class StateStore(SQLBaseStore):
 
         defer.returnValue(results)
 
+
+class StateStore(StateGroupReadStore, BackgroundUpdateStore):
+    """ Keeps track of the state at a given event.
+
+    This is done by the concept of `state groups`. Every event is a assigned
+    a state group (identified by an arbitrary string), which references a
+    collection of state events. The current state of an event is then the
+    collection of state events referenced by the event's state group.
+
+    Hence, every change in the current state causes a new state group to be
+    generated. However, if no change happens (e.g., if we get a message event
+    with only one parent it inherits the state group from its parent.)
+
+    There are three tables:
+      * `state_groups`: Stores group name, first event with in the group and
+        room id.
+      * `event_to_state_groups`: Maps events to state groups.
+      * `state_groups_state`: Maps state group to state events.
+    """
+
+    STATE_GROUP_DEDUPLICATION_UPDATE_NAME = "state_group_state_deduplication"
+    STATE_GROUP_INDEX_UPDATE_NAME = "state_group_state_type_index"
+    CURRENT_STATE_INDEX_UPDATE_NAME = "current_state_members_idx"
+
+    def __init__(self, db_conn, hs):
+        super(StateStore, self).__init__(db_conn, hs)
+        self.register_background_update_handler(
+            self.STATE_GROUP_DEDUPLICATION_UPDATE_NAME,
+            self._background_deduplicate_state,
+        )
+        self.register_background_update_handler(
+            self.STATE_GROUP_INDEX_UPDATE_NAME,
+            self._background_index_state,
+        )
+        self.register_background_index_update(
+            self.CURRENT_STATE_INDEX_UPDATE_NAME,
+            index_name="current_state_events_member_index",
+            table="current_state_events",
+            columns=["state_key"],
+            where_clause="type='m.room.member'",
+        )
+
+    def _have_persisted_state_group_txn(self, txn, state_group):
+        txn.execute(
+            "SELECT count(*) FROM state_groups WHERE id = ?",
+            (state_group,)
+        )
+        row = txn.fetchone()
+        return row and row[0]
+
+    def _store_mult_state_groups_txn(self, txn, events_and_contexts):
+        state_groups = {}
+        for event, context in events_and_contexts:
+            if event.internal_metadata.is_outlier():
+                continue
+
+            if context.current_state_ids is None:
+                # AFAIK, this can never happen
+                logger.error(
+                    "Non-outlier event %s had current_state_ids==None",
+                    event.event_id)
+                continue
+
+            # if the event was rejected, just give it the same state as its
+            # predecessor.
+            if context.rejected:
+                state_groups[event.event_id] = context.prev_group
+                continue
+
+            state_groups[event.event_id] = context.state_group
+
+            if self._have_persisted_state_group_txn(txn, context.state_group):
+                continue
+
+            self._simple_insert_txn(
+                txn,
+                table="state_groups",
+                values={
+                    "id": context.state_group,
+                    "room_id": event.room_id,
+                    "event_id": event.event_id,
+                },
+            )
+
+            # We persist as a delta if we can, while also ensuring the chain
+            # of deltas isn't tooo long, as otherwise read performance degrades.
+            if context.prev_group:
+                is_in_db = self._simple_select_one_onecol_txn(
+                    txn,
+                    table="state_groups",
+                    keyvalues={"id": context.prev_group},
+                    retcol="id",
+                    allow_none=True,
+                )
+                if not is_in_db:
+                    raise Exception(
+                        "Trying to persist state with unpersisted prev_group: %r"
+                        % (context.prev_group,)
+                    )
+
+                potential_hops = self._count_state_group_hops_txn(
+                    txn, context.prev_group
+                )
+            if context.prev_group and potential_hops < MAX_STATE_DELTA_HOPS:
+                self._simple_insert_txn(
+                    txn,
+                    table="state_group_edges",
+                    values={
+                        "state_group": context.state_group,
+                        "prev_state_group": context.prev_group,
+                    },
+                )
+
+                self._simple_insert_many_txn(
+                    txn,
+                    table="state_groups_state",
+                    values=[
+                        {
+                            "state_group": context.state_group,
+                            "room_id": event.room_id,
+                            "type": key[0],
+                            "state_key": key[1],
+                            "event_id": state_id,
+                        }
+                        for key, state_id in context.delta_ids.iteritems()
+                    ],
+                )
+            else:
+                self._simple_insert_many_txn(
+                    txn,
+                    table="state_groups_state",
+                    values=[
+                        {
+                            "state_group": context.state_group,
+                            "room_id": event.room_id,
+                            "type": key[0],
+                            "state_key": key[1],
+                            "event_id": state_id,
+                        }
+                        for key, state_id in context.current_state_ids.iteritems()
+                    ],
+                )
+
+            # Prefill the state group cache with this group.
+            # It's fine to use the sequence like this as the state group map
+            # is immutable. (If the map wasn't immutable then this prefill could
+            # race with another update)
+            txn.call_after(
+                self._state_group_cache.update,
+                self._state_group_cache.sequence,
+                key=context.state_group,
+                value=dict(context.current_state_ids),
+                full=True,
+            )
+
+        self._simple_insert_many_txn(
+            txn,
+            table="event_to_state_groups",
+            values=[
+                {
+                    "state_group": state_group_id,
+                    "event_id": event_id,
+                }
+                for event_id, state_group_id in state_groups.iteritems()
+            ],
+        )
+
+        for event_id, state_group_id in state_groups.iteritems():
+            txn.call_after(
+                self._get_state_group_for_event.prefill,
+                (event_id,), state_group_id
+            )
+
+    def _count_state_group_hops_txn(self, txn, state_group):
+        """Given a state group, count how many hops there are in the tree.
+
+        This is used to ensure the delta chains don't get too long.
+        """
+        if isinstance(self.database_engine, PostgresEngine):
+            sql = ("""
+                WITH RECURSIVE state(state_group) AS (
+                    VALUES(?::bigint)
+                    UNION ALL
+                    SELECT prev_state_group FROM state_group_edges e, state s
+                    WHERE s.state_group = e.state_group
+                )
+                SELECT count(*) FROM state;
+            """)
+
+            txn.execute(sql, (state_group,))
+            row = txn.fetchone()
+            if row and row[0]:
+                return row[0]
+            else:
+                return 0
+        else:
+            # We don't use WITH RECURSIVE on sqlite3 as there are distributions
+            # that ship with an sqlite3 version that doesn't support it (e.g. wheezy)
+            next_group = state_group
+            count = 0
+
+            while next_group:
+                next_group = self._simple_select_one_onecol_txn(
+                    txn,
+                    table="state_group_edges",
+                    keyvalues={"state_group": next_group},
+                    retcol="prev_state_group",
+                    allow_none=True,
+                )
+                if next_group:
+                    count += 1
+
+            return count
+
     def get_next_state_group(self):
         return self._state_groups_id_gen.get_next()
 
diff --git a/synapse/storage/stream.py b/synapse/storage/stream.py
index dddd5fc0e7..52bdce5be2 100644
--- a/synapse/storage/stream.py
+++ b/synapse/storage/stream.py
@@ -39,7 +39,7 @@ from ._base import SQLBaseStore
 from synapse.util.caches.descriptors import cached
 from synapse.api.constants import EventTypes
 from synapse.types import RoomStreamToken
-from synapse.util.logcontext import preserve_fn, preserve_context_over_deferred
+from synapse.util.logcontext import make_deferred_yieldable, preserve_fn
 from synapse.storage.engines import PostgresEngine, Sqlite3Engine
 
 import logging
@@ -234,7 +234,7 @@ class StreamStore(SQLBaseStore):
         results = {}
         room_ids = list(room_ids)
         for rm_ids in (room_ids[i:i + 20] for i in xrange(0, len(room_ids), 20)):
-            res = yield preserve_context_over_deferred(defer.gatherResults([
+            res = yield make_deferred_yieldable(defer.gatherResults([
                 preserve_fn(self.get_room_events_stream_for_room)(
                     room_id, from_key, to_key, limit, order=order,
                 )
diff --git a/synapse/storage/transactions.py b/synapse/storage/transactions.py
index 809fdd311f..8f61f7ffae 100644
--- a/synapse/storage/transactions.py
+++ b/synapse/storage/transactions.py
@@ -46,8 +46,8 @@ class TransactionStore(SQLBaseStore):
     """A collection of queries for handling PDUs.
     """
 
-    def __init__(self, hs):
-        super(TransactionStore, self).__init__(hs)
+    def __init__(self, db_conn, hs):
+        super(TransactionStore, self).__init__(db_conn, hs)
 
         self._clock.looping_call(self._cleanup_transactions, 30 * 60 * 1000)
 
diff --git a/synapse/storage/user_directory.py b/synapse/storage/user_directory.py
index 2a4db3f03c..c9bff408ef 100644
--- a/synapse/storage/user_directory.py
+++ b/synapse/storage/user_directory.py
@@ -63,7 +63,7 @@ class UserDirectoryStore(SQLBaseStore):
             user_ids (list(str)): Users to add
         """
         yield self._simple_insert_many(
-            table="users_in_pubic_room",
+            table="users_in_public_rooms",
             values=[
                 {
                     "user_id": user_id,
@@ -164,7 +164,7 @@ class UserDirectoryStore(SQLBaseStore):
             )
 
             if isinstance(self.database_engine, PostgresEngine):
-                # We weight the loclpart most highly, then display name and finally
+                # We weight the localpart most highly, then display name and finally
                 # server name
                 if new_entry:
                     sql = """
@@ -219,7 +219,7 @@ class UserDirectoryStore(SQLBaseStore):
     @defer.inlineCallbacks
     def update_user_in_public_user_list(self, user_id, room_id):
         yield self._simple_update_one(
-            table="users_in_pubic_room",
+            table="users_in_public_rooms",
             keyvalues={"user_id": user_id},
             updatevalues={"room_id": room_id},
             desc="update_user_in_public_user_list",
@@ -240,7 +240,7 @@ class UserDirectoryStore(SQLBaseStore):
             )
             self._simple_delete_txn(
                 txn,
-                table="users_in_pubic_room",
+                table="users_in_public_rooms",
                 keyvalues={"user_id": user_id},
             )
             txn.call_after(
@@ -256,7 +256,7 @@ class UserDirectoryStore(SQLBaseStore):
     @defer.inlineCallbacks
     def remove_from_user_in_public_room(self, user_id):
         yield self._simple_delete(
-            table="users_in_pubic_room",
+            table="users_in_public_rooms",
             keyvalues={"user_id": user_id},
             desc="remove_from_user_in_public_room",
         )
@@ -267,7 +267,7 @@ class UserDirectoryStore(SQLBaseStore):
         in the given room_id
         """
         return self._simple_select_onecol(
-            table="users_in_pubic_room",
+            table="users_in_public_rooms",
             keyvalues={"room_id": room_id},
             retcol="user_id",
             desc="get_users_in_public_due_to_room",
@@ -286,7 +286,7 @@ class UserDirectoryStore(SQLBaseStore):
         )
 
         user_ids_pub = yield self._simple_select_onecol(
-            table="users_in_pubic_room",
+            table="users_in_public_rooms",
             keyvalues={"room_id": room_id},
             retcol="user_id",
             desc="get_users_in_dir_due_to_room",
@@ -317,6 +317,16 @@ class UserDirectoryStore(SQLBaseStore):
         rows = yield self._execute("get_all_rooms", None, sql)
         defer.returnValue([room_id for room_id, in rows])
 
+    @defer.inlineCallbacks
+    def get_all_local_users(self):
+        """Get all local users
+        """
+        sql = """
+            SELECT name FROM users
+        """
+        rows = yield self._execute("get_all_local_users", None, sql)
+        defer.returnValue([name for name, in rows])
+
     def add_users_who_share_room(self, room_id, share_private, user_id_tuples):
         """Insert entries into the users_who_share_rooms table. The first
         user should be a local user.
@@ -514,7 +524,7 @@ class UserDirectoryStore(SQLBaseStore):
         def _delete_all_from_user_dir_txn(txn):
             txn.execute("DELETE FROM user_directory")
             txn.execute("DELETE FROM user_directory_search")
-            txn.execute("DELETE FROM users_in_pubic_room")
+            txn.execute("DELETE FROM users_in_public_rooms")
             txn.execute("DELETE FROM users_who_share_rooms")
             txn.call_after(self.get_user_in_directory.invalidate_all)
             txn.call_after(self.get_user_in_public_room.invalidate_all)
@@ -537,7 +547,7 @@ class UserDirectoryStore(SQLBaseStore):
     @cached()
     def get_user_in_public_room(self, user_id):
         return self._simple_select_one(
-            table="users_in_pubic_room",
+            table="users_in_public_rooms",
             keyvalues={"user_id": user_id},
             retcols=("room_id",),
             allow_none=True,
@@ -629,6 +639,20 @@ class UserDirectoryStore(SQLBaseStore):
                     ]
                 }
         """
+
+        if self.hs.config.user_directory_search_all_users:
+            join_clause = ""
+            where_clause = "?<>''"  # naughty hack to keep the same number of binds
+        else:
+            join_clause = """
+                LEFT JOIN users_in_public_rooms AS p USING (user_id)
+                LEFT JOIN (
+                    SELECT other_user_id AS user_id FROM users_who_share_rooms
+                    WHERE user_id = ? AND share_private
+                ) AS s USING (user_id)
+            """
+            where_clause = "(s.user_id IS NOT NULL OR p.user_id IS NOT NULL)"
+
         if isinstance(self.database_engine, PostgresEngine):
             full_query, exact_query, prefix_query = _parse_query_postgres(search_term)
 
@@ -641,13 +665,9 @@ class UserDirectoryStore(SQLBaseStore):
                 SELECT d.user_id, display_name, avatar_url
                 FROM user_directory_search
                 INNER JOIN user_directory AS d USING (user_id)
-                LEFT JOIN users_in_pubic_room AS p USING (user_id)
-                LEFT JOIN (
-                    SELECT other_user_id AS user_id FROM users_who_share_rooms
-                    WHERE user_id = ? AND share_private
-                ) AS s USING (user_id)
+                %s
                 WHERE
-                    (s.user_id IS NOT NULL OR p.user_id IS NOT NULL)
+                    %s
                     AND vector @@ to_tsquery('english', ?)
                 ORDER BY
                     (CASE WHEN s.user_id IS NOT NULL THEN 4.0 ELSE 1.0 END)
@@ -671,7 +691,7 @@ class UserDirectoryStore(SQLBaseStore):
                     display_name IS NULL,
                     avatar_url IS NULL
                 LIMIT ?
-            """
+            """ % (join_clause, where_clause)
             args = (user_id, full_query, exact_query, prefix_query, limit + 1,)
         elif isinstance(self.database_engine, Sqlite3Engine):
             search_query = _parse_query_sqlite(search_term)
@@ -680,20 +700,16 @@ class UserDirectoryStore(SQLBaseStore):
                 SELECT d.user_id, display_name, avatar_url
                 FROM user_directory_search
                 INNER JOIN user_directory AS d USING (user_id)
-                LEFT JOIN users_in_pubic_room AS p USING (user_id)
-                LEFT JOIN (
-                    SELECT other_user_id AS user_id FROM users_who_share_rooms
-                    WHERE user_id = ? AND share_private
-                ) AS s USING (user_id)
+                %s
                 WHERE
-                    (s.user_id IS NOT NULL OR p.user_id IS NOT NULL)
+                    %s
                     AND value MATCH ?
                 ORDER BY
                     rank(matchinfo(user_directory_search)) DESC,
                     display_name IS NULL,
                     avatar_url IS NULL
                 LIMIT ?
-            """
+            """ % (join_clause, where_clause)
             args = (user_id, search_query, limit + 1)
         else:
             # This should be unreachable.
@@ -723,7 +739,7 @@ def _parse_query_sqlite(search_term):
 
     # Pull out the individual words, discarding any non-word characters.
     results = re.findall(r"([\w\-]+)", search_term, re.UNICODE)
-    return " & ".join("(%s* | %s)" % (result, result,) for result in results)
+    return " & ".join("(%s* OR %s)" % (result, result,) for result in results)
 
 
 def _parse_query_postgres(search_term):
diff --git a/synapse/streams/config.py b/synapse/streams/config.py
index 4f089bfb94..ca78e551cb 100644
--- a/synapse/streams/config.py
+++ b/synapse/streams/config.py
@@ -80,13 +80,13 @@ class PaginationConfig(object):
                 from_tok = None  # For backwards compat.
             elif from_tok:
                 from_tok = StreamToken.from_string(from_tok)
-        except:
+        except Exception:
             raise SynapseError(400, "'from' paramater is invalid")
 
         try:
             if to_tok:
                 to_tok = StreamToken.from_string(to_tok)
-        except:
+        except Exception:
             raise SynapseError(400, "'to' paramater is invalid")
 
         limit = get_param("limit", None)
@@ -98,7 +98,7 @@ class PaginationConfig(object):
 
         try:
             return PaginationConfig(from_tok, to_tok, direction, limit)
-        except:
+        except Exception:
             logger.exception("Failed to create pagination config")
             raise SynapseError(400, "Invalid request.")
 
diff --git a/synapse/streams/events.py b/synapse/streams/events.py
index 91a59b0bae..f03ad99118 100644
--- a/synapse/streams/events.py
+++ b/synapse/streams/events.py
@@ -45,6 +45,7 @@ class EventSources(object):
         push_rules_key, _ = self.store.get_push_rules_stream_token()
         to_device_key = self.store.get_to_device_stream_token()
         device_list_key = self.store.get_device_stream_token()
+        groups_key = self.store.get_group_stream_token()
 
         token = StreamToken(
             room_key=(
@@ -65,6 +66,7 @@ class EventSources(object):
             push_rules_key=push_rules_key,
             to_device_key=to_device_key,
             device_list_key=device_list_key,
+            groups_key=groups_key,
         )
         defer.returnValue(token)
 
@@ -73,6 +75,7 @@ class EventSources(object):
         push_rules_key, _ = self.store.get_push_rules_stream_token()
         to_device_key = self.store.get_to_device_stream_token()
         device_list_key = self.store.get_device_stream_token()
+        groups_key = self.store.get_group_stream_token()
 
         token = StreamToken(
             room_key=(
@@ -93,5 +96,6 @@ class EventSources(object):
             push_rules_key=push_rules_key,
             to_device_key=to_device_key,
             device_list_key=device_list_key,
+            groups_key=groups_key,
         )
         defer.returnValue(token)
diff --git a/synapse/types.py b/synapse/types.py
index 111948540d..6e76c016d9 100644
--- a/synapse/types.py
+++ b/synapse/types.py
@@ -12,6 +12,7 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
+import string
 
 from synapse.api.errors import SynapseError
 
@@ -126,15 +127,11 @@ class DomainSpecificString(
         try:
             cls.from_string(s)
             return True
-        except:
+        except Exception:
             return False
 
     __str__ = to_string
 
-    @classmethod
-    def create(cls, localpart, domain,):
-        return cls(localpart=localpart, domain=domain)
-
 
 class UserID(DomainSpecificString):
     """Structure representing a user ID."""
@@ -156,6 +153,43 @@ class EventID(DomainSpecificString):
     SIGIL = "$"
 
 
+class GroupID(DomainSpecificString):
+    """Structure representing a group ID."""
+    SIGIL = "+"
+
+    @classmethod
+    def from_string(cls, s):
+        group_id = super(GroupID, cls).from_string(s)
+        if not group_id.localpart:
+            raise SynapseError(
+                400,
+                "Group ID cannot be empty",
+            )
+
+        if contains_invalid_mxid_characters(group_id.localpart):
+            raise SynapseError(
+                400,
+                "Group ID can only contain characters a-z, 0-9, or '=_-./'",
+            )
+
+        return group_id
+
+
+mxid_localpart_allowed_characters = set("_-./=" + string.ascii_lowercase + string.digits)
+
+
+def contains_invalid_mxid_characters(localpart):
+    """Check for characters not allowed in an mxid or groupid localpart
+
+    Args:
+        localpart (basestring): the localpart to be checked
+
+    Returns:
+        bool: True if there are any naughty characters
+    """
+    return any(c not in mxid_localpart_allowed_characters for c in localpart)
+
+
 class StreamToken(
     namedtuple("Token", (
         "room_key",
@@ -166,6 +200,7 @@ class StreamToken(
         "push_rules_key",
         "to_device_key",
         "device_list_key",
+        "groups_key",
     ))
 ):
     _SEPARATOR = "_"
@@ -178,7 +213,7 @@ class StreamToken(
                 # i.e. old token from before receipt_key
                 keys.append("0")
             return cls(*keys)
-        except:
+        except Exception:
             raise SynapseError(400, "Invalid Token")
 
     def to_string(self):
@@ -204,6 +239,7 @@ class StreamToken(
             or (int(other.push_rules_key) < int(self.push_rules_key))
             or (int(other.to_device_key) < int(self.to_device_key))
             or (int(other.device_list_key) < int(self.device_list_key))
+            or (int(other.groups_key) < int(self.groups_key))
         )
 
     def copy_and_advance(self, key, new_value):
@@ -263,7 +299,7 @@ class RoomStreamToken(namedtuple("_StreamToken", "topological stream")):
             if string[0] == 't':
                 parts = string[1:].split('-', 1)
                 return cls(topological=int(parts[0]), stream=int(parts[1]))
-        except:
+        except Exception:
             pass
         raise SynapseError(400, "Invalid token %r" % (string,))
 
@@ -272,7 +308,7 @@ class RoomStreamToken(namedtuple("_StreamToken", "topological stream")):
         try:
             if string[0] == 's':
                 return cls(topological=None, stream=int(string[1:]))
-        except:
+        except Exception:
             pass
         raise SynapseError(400, "Invalid token %r" % (string,))
 
diff --git a/synapse/util/__init__.py b/synapse/util/__init__.py
index 2a2360ab5d..756d8ffa32 100644
--- a/synapse/util/__init__.py
+++ b/synapse/util/__init__.py
@@ -59,9 +59,9 @@ class Clock(object):
             f(function): The function to call repeatedly.
             msec(float): How long to wait between calls in milliseconds.
         """
-        l = task.LoopingCall(f)
-        l.start(msec / 1000.0, now=False)
-        return l
+        call = task.LoopingCall(f)
+        call.start(msec / 1000.0, now=False)
+        return call
 
     def call_later(self, delay, callback, *args, **kwargs):
         """Call something later
@@ -82,7 +82,7 @@ class Clock(object):
     def cancel_call_later(self, timer, ignore_errs=False):
         try:
             timer.cancel()
-        except:
+        except Exception:
             if not ignore_errs:
                 raise
 
@@ -97,12 +97,12 @@ class Clock(object):
 
             try:
                 ret_deferred.errback(e)
-            except:
+            except Exception:
                 pass
 
             try:
                 given_deferred.cancel()
-            except:
+            except Exception:
                 pass
 
         timer = None
@@ -110,7 +110,7 @@ class Clock(object):
         def cancel(res):
             try:
                 self.cancel_call_later(timer)
-            except:
+            except Exception:
                 pass
             return res
 
@@ -119,7 +119,7 @@ class Clock(object):
         def success(res):
             try:
                 ret_deferred.callback(res)
-            except:
+            except Exception:
                 pass
 
             return res
@@ -127,7 +127,7 @@ class Clock(object):
         def err(res):
             try:
                 ret_deferred.errback(res)
-            except:
+            except Exception:
                 pass
 
         given_deferred.addCallbacks(callback=success, errback=err)
diff --git a/synapse/util/async.py b/synapse/util/async.py
index 1453faf0ef..0729bb2863 100644
--- a/synapse/util/async.py
+++ b/synapse/util/async.py
@@ -17,9 +17,9 @@
 from twisted.internet import defer, reactor
 
 from .logcontext import (
-    PreserveLoggingContext, preserve_fn, preserve_context_over_deferred,
+    PreserveLoggingContext, make_deferred_yieldable, preserve_fn
 )
-from synapse.util import unwrapFirstError
+from synapse.util import logcontext, unwrapFirstError
 
 from contextlib import contextmanager
 
@@ -53,6 +53,11 @@ class ObservableDeferred(object):
 
     Cancelling or otherwise resolving an observer will not affect the original
     ObservableDeferred.
+
+    NB that it does not attempt to do anything with logcontexts; in general
+    you should probably make_deferred_yieldable the deferreds
+    returned by `observe`, and ensure that the original deferred runs its
+    callbacks in the sentinel logcontext.
     """
 
     __slots__ = ["_deferred", "_observers", "_result"]
@@ -68,7 +73,7 @@ class ObservableDeferred(object):
                 try:
                     # TODO: Handle errors here.
                     self._observers.pop().callback(r)
-                except:
+                except Exception:
                     pass
             return r
 
@@ -78,7 +83,7 @@ class ObservableDeferred(object):
                 try:
                     # TODO: Handle errors here.
                     self._observers.pop().errback(f)
-                except:
+                except Exception:
                     pass
 
             if consumeErrors:
@@ -155,7 +160,7 @@ def concurrently_execute(func, args, limit):
         except StopIteration:
             pass
 
-    return preserve_context_over_deferred(defer.gatherResults([
+    return logcontext.make_deferred_yieldable(defer.gatherResults([
         preserve_fn(_concurrently_execute_inner)()
         for _ in xrange(limit)
     ], consumeErrors=True)).addErrback(unwrapFirstError)
@@ -200,10 +205,29 @@ class Linearizer(object):
             try:
                 with PreserveLoggingContext():
                     yield current_defer
-            except:
+            except Exception:
                 logger.exception("Unexpected exception in Linearizer")
 
-        logger.info("Acquired linearizer lock %r for key %r", self.name, key)
+            logger.info("Acquired linearizer lock %r for key %r", self.name,
+                        key)
+
+            # if the code holding the lock completes synchronously, then it
+            # will recursively run the next claimant on the list. That can
+            # relatively rapidly lead to stack exhaustion. This is essentially
+            # the same problem as http://twistedmatrix.com/trac/ticket/9304.
+            #
+            # In order to break the cycle, we add a cheeky sleep(0) here to
+            # ensure that we fall back to the reactor between each iteration.
+            #
+            # (There's no particular need for it to happen before we return
+            # the context manager, but it needs to happen while we hold the
+            # lock, and the context manager's exit code must be synchronous,
+            # so actually this is the only sensible place.
+            yield run_on_reactor()
+
+        else:
+            logger.info("Acquired uncontended linearizer lock %r for key %r",
+                        self.name, key)
 
         @contextmanager
         def _ctx_manager():
@@ -211,7 +235,8 @@ class Linearizer(object):
                 yield
             finally:
                 logger.info("Releasing linearizer lock %r for key %r", self.name, key)
-                new_defer.callback(None)
+                with PreserveLoggingContext():
+                    new_defer.callback(None)
                 current_d = self.key_to_defer.get(key)
                 if current_d is new_defer:
                     self.key_to_defer.pop(key, None)
@@ -253,8 +278,13 @@ class Limiter(object):
         if entry[0] >= self.max_count:
             new_defer = defer.Deferred()
             entry[1].append(new_defer)
+
+            logger.info("Waiting to acquire limiter lock for key %r", key)
             with PreserveLoggingContext():
                 yield new_defer
+            logger.info("Acquired limiter lock for key %r", key)
+        else:
+            logger.info("Acquired uncontended limiter lock for key %r", key)
 
         entry[0] += 1
 
@@ -263,16 +293,21 @@ class Limiter(object):
             try:
                 yield
             finally:
+                logger.info("Releasing limiter lock for key %r", key)
+
                 # We've finished executing so check if there are any things
                 # blocked waiting to execute and start one of them
                 entry[0] -= 1
-                try:
-                    entry[1].pop(0).callback(None)
-                except IndexError:
-                    # If nothing else is executing for this key then remove it
-                    # from the map
-                    if entry[0] == 0:
-                        self.key_to_defer.pop(key, None)
+
+                if entry[1]:
+                    next_def = entry[1].pop(0)
+
+                    with PreserveLoggingContext():
+                        next_def.callback(None)
+                elif entry[0] == 0:
+                    # We were the last thing for this key: remove it from the
+                    # map.
+                    del self.key_to_defer[key]
 
         defer.returnValue(_ctx_manager())
 
@@ -316,7 +351,7 @@ class ReadWriteLock(object):
 
         # We wait for the latest writer to finish writing. We can safely ignore
         # any existing readers... as they're readers.
-        yield curr_writer
+        yield make_deferred_yieldable(curr_writer)
 
         @contextmanager
         def _ctx_manager():
@@ -345,7 +380,7 @@ class ReadWriteLock(object):
         curr_readers.clear()
         self.key_to_current_writer[key] = new_defer
 
-        yield preserve_context_over_deferred(defer.gatherResults(to_wait_on))
+        yield make_deferred_yieldable(defer.gatherResults(to_wait_on))
 
         @contextmanager
         def _ctx_manager():
diff --git a/synapse/util/distributor.py b/synapse/util/distributor.py
index e68f94ce77..734331caaa 100644
--- a/synapse/util/distributor.py
+++ b/synapse/util/distributor.py
@@ -13,32 +13,24 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-from twisted.internet import defer
+import logging
 
-from synapse.util.logcontext import (
-    PreserveLoggingContext, preserve_context_over_fn
-)
+from twisted.internet import defer
 
 from synapse.util import unwrapFirstError
-
-import logging
-
+from synapse.util.logcontext import PreserveLoggingContext
 
 logger = logging.getLogger(__name__)
 
 
 def user_left_room(distributor, user, room_id):
-    return preserve_context_over_fn(
-        distributor.fire,
-        "user_left_room", user=user, room_id=room_id
-    )
+    with PreserveLoggingContext():
+        distributor.fire("user_left_room", user=user, room_id=room_id)
 
 
 def user_joined_room(distributor, user, room_id):
-    return preserve_context_over_fn(
-        distributor.fire,
-        "user_joined_room", user=user, room_id=room_id
-    )
+    with PreserveLoggingContext():
+        distributor.fire("user_joined_room", user=user, room_id=room_id)
 
 
 class Distributor(object):
diff --git a/synapse/util/logcontext.py b/synapse/util/logcontext.py
index 990216145e..48c9f6802d 100644
--- a/synapse/util/logcontext.py
+++ b/synapse/util/logcontext.py
@@ -42,7 +42,7 @@ try:
 
     def get_thread_resource_usage():
         return resource.getrusage(RUSAGE_THREAD)
-except:
+except Exception:
     # If the system doesn't support resource.getrusage(RUSAGE_THREAD) then we
     # won't track resource usage by returning None.
     def get_thread_resource_usage():
@@ -261,67 +261,6 @@ class PreserveLoggingContext(object):
                 )
 
 
-class _PreservingContextDeferred(defer.Deferred):
-    """A deferred that ensures that all callbacks and errbacks are called with
-    the given logging context.
-    """
-    def __init__(self, context):
-        self._log_context = context
-        defer.Deferred.__init__(self)
-
-    def addCallbacks(self, callback, errback=None,
-                     callbackArgs=None, callbackKeywords=None,
-                     errbackArgs=None, errbackKeywords=None):
-        callback = self._wrap_callback(callback)
-        errback = self._wrap_callback(errback)
-        return defer.Deferred.addCallbacks(
-            self, callback,
-            errback=errback,
-            callbackArgs=callbackArgs,
-            callbackKeywords=callbackKeywords,
-            errbackArgs=errbackArgs,
-            errbackKeywords=errbackKeywords,
-        )
-
-    def _wrap_callback(self, f):
-        def g(res, *args, **kwargs):
-            with PreserveLoggingContext(self._log_context):
-                res = f(res, *args, **kwargs)
-            return res
-        return g
-
-
-def preserve_context_over_fn(fn, *args, **kwargs):
-    """Takes a function and invokes it with the given arguments, but removes
-    and restores the current logging context while doing so.
-
-    If the result is a deferred, call preserve_context_over_deferred before
-    returning it.
-    """
-    with PreserveLoggingContext():
-        res = fn(*args, **kwargs)
-
-    if isinstance(res, defer.Deferred):
-        return preserve_context_over_deferred(res)
-    else:
-        return res
-
-
-def preserve_context_over_deferred(deferred, context=None):
-    """Given a deferred wrap it such that any callbacks added later to it will
-    be invoked with the current context.
-
-    Deprecated: this almost certainly doesn't do want you want, ie make
-    the deferred follow the synapse logcontext rules: try
-    ``make_deferred_yieldable`` instead.
-    """
-    if context is None:
-        context = LoggingContext.current_context()
-    d = _PreservingContextDeferred(context)
-    deferred.chainDeferred(d)
-    return d
-
-
 def preserve_fn(f):
     """Wraps a function, to ensure that the current context is restored after
     return from the function, and that the sentinel context is set once the
diff --git a/synapse/util/logformatter.py b/synapse/util/logformatter.py
new file mode 100644
index 0000000000..cdbc4bffd7
--- /dev/null
+++ b/synapse/util/logformatter.py
@@ -0,0 +1,51 @@
+# -*- coding: utf-8 -*-
+# Copyright 2017 New Vector Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+
+import StringIO
+import logging
+import traceback
+
+
+class LogFormatter(logging.Formatter):
+    """Log formatter which gives more detail for exceptions
+
+    This is the same as the standard log formatter, except that when logging
+    exceptions [typically via log.foo("msg", exc_info=1)], it prints the
+    sequence that led up to the point at which the exception was caught.
+    (Normally only stack frames between the point the exception was raised and
+    where it was caught are logged).
+    """
+    def __init__(self, *args, **kwargs):
+        super(LogFormatter, self).__init__(*args, **kwargs)
+
+    def formatException(self, ei):
+        sio = StringIO.StringIO()
+        (typ, val, tb) = ei
+
+        # log the stack above the exception capture point if possible, but
+        # check that we actually have an f_back attribute to work around
+        # https://twistedmatrix.com/trac/ticket/9305
+
+        if tb and hasattr(tb.tb_frame, 'f_back'):
+            sio.write("Capture point (most recent call last):\n")
+            traceback.print_stack(tb.tb_frame.f_back, None, sio)
+
+        traceback.print_exception(typ, val, tb, None, sio)
+        s = sio.getvalue()
+        sio.close()
+        if s[-1:] == "\n":
+            s = s[:-1]
+        return s
diff --git a/synapse/util/retryutils.py b/synapse/util/retryutils.py
index 4fa9d1a03c..1adedbb361 100644
--- a/synapse/util/retryutils.py
+++ b/synapse/util/retryutils.py
@@ -189,7 +189,7 @@ class RetryDestinationLimiter(object):
                 yield self.store.set_destination_retry_timings(
                     self.destination, retry_last_ts, self.retry_interval
                 )
-            except:
+            except Exception:
                 logger.exception(
                     "Failed to store set_destination_retry_timings",
                 )
diff --git a/synapse/util/wheel_timer.py b/synapse/util/wheel_timer.py
index 7412fc57a4..b70f9a6b0a 100644
--- a/synapse/util/wheel_timer.py
+++ b/synapse/util/wheel_timer.py
@@ -91,7 +91,4 @@ class WheelTimer(object):
         return ret
 
     def __len__(self):
-        l = 0
-        for entry in self.entries:
-            l += len(entry.queue)
-        return l
+        return sum(len(entry.queue) for entry in self.entries)
diff --git a/synapse/visibility.py b/synapse/visibility.py
index d7dbdc77ff..aaca2c584c 100644
--- a/synapse/visibility.py
+++ b/synapse/visibility.py
@@ -17,7 +17,7 @@ from twisted.internet import defer
 
 from synapse.api.constants import Membership, EventTypes
 
-from synapse.util.logcontext import preserve_fn, preserve_context_over_deferred
+from synapse.util.logcontext import make_deferred_yieldable, preserve_fn
 
 import logging
 
@@ -58,7 +58,7 @@ def filter_events_for_clients(store, user_tuples, events, event_id_to_state,
         always_include_ids (set(event_id)): set of event ids to specifically
             include (unless sender is ignored)
     """
-    forgotten = yield preserve_context_over_deferred(defer.gatherResults([
+    forgotten = yield make_deferred_yieldable(defer.gatherResults([
         defer.maybeDeferred(
             preserve_fn(store.who_forgot_in_room),
             room_id,