diff --git a/latest/development/contributing_guide.html b/latest/development/contributing_guide.html
index 3aeafe7b4d..431123734e 100644
--- a/latest/development/contributing_guide.html
+++ b/latest/development/contributing_guide.html
@@ -76,7 +76,7 @@
<nav id="sidebar" class="sidebar" aria-label="Table of contents">
<div class="sidebar-scrollbox">
- <ol class="chapter"><li class="chapter-item expanded affix "><li class="part-title">Introduction</li><li class="chapter-item expanded "><a href="../welcome_and_overview.html">Welcome and Overview</a></li><li class="chapter-item expanded affix "><li class="part-title">Setup</li><li class="chapter-item expanded "><a href="../setup/installation.html">Installation</a></li><li class="chapter-item expanded "><a href="../postgres.html">Using Postgres</a></li><li class="chapter-item expanded "><a href="../reverse_proxy.html">Configuring a Reverse Proxy</a></li><li class="chapter-item expanded "><a href="../setup/forward_proxy.html">Configuring a Forward/Outbound Proxy</a></li><li class="chapter-item expanded "><a href="../turn-howto.html">Configuring a Turn Server</a></li><li class="chapter-item expanded "><a href="../delegate.html">Delegation</a></li><li class="chapter-item expanded affix "><li class="part-title">Upgrading</li><li class="chapter-item expanded "><a href="../upgrade.html">Upgrading between Synapse Versions</a></li><li class="chapter-item expanded affix "><li class="part-title">Usage</li><li class="chapter-item expanded "><a href="../federate.html">Federation</a></li><li class="chapter-item expanded "><a href="../usage/configuration/index.html">Configuration</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../usage/configuration/config_documentation.html">Configuration Manual</a></li><li class="chapter-item expanded "><a href="../usage/configuration/homeserver_sample_config.html">Homeserver Sample Config File</a></li><li class="chapter-item expanded "><a href="../usage/configuration/logging_sample_config.html">Logging Sample Config File</a></li><li class="chapter-item expanded "><a href="../structured_logging.html">Structured Logging</a></li><li class="chapter-item expanded "><a href="../templates.html">Templates</a></li><li class="chapter-item expanded "><a href="../usage/configuration/user_authentication/index.html">User Authentication</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../usage/configuration/user_authentication/single_sign_on/index.html">Single-Sign On</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../openid.html">OpenID Connect</a></li><li class="chapter-item expanded "><a href="../usage/configuration/user_authentication/single_sign_on/saml.html">SAML</a></li><li class="chapter-item expanded "><a href="../usage/configuration/user_authentication/single_sign_on/cas.html">CAS</a></li><li class="chapter-item expanded "><a href="../sso_mapping_providers.html">SSO Mapping Providers</a></li></ol></li><li class="chapter-item expanded "><a href="../password_auth_providers.html">Password Auth Providers</a></li><li class="chapter-item expanded "><a href="../jwt.html">JSON Web Tokens</a></li><li class="chapter-item expanded "><a href="../usage/configuration/user_authentication/refresh_tokens.html">Refresh Tokens</a></li></ol></li><li class="chapter-item expanded "><a href="../CAPTCHA_SETUP.html">Registration Captcha</a></li><li class="chapter-item expanded "><a href="../application_services.html">Application Services</a></li><li class="chapter-item expanded "><a href="../server_notices.html">Server Notices</a></li><li class="chapter-item expanded "><a href="../consent_tracking.html">Consent Tracking</a></li><li class="chapter-item expanded "><a href="../development/url_previews.html">URL Previews</a></li><li class="chapter-item expanded "><a href="../user_directory.html">User Directory</a></li><li class="chapter-item expanded "><a href="../message_retention_policies.html">Message Retention Policies</a></li><li class="chapter-item expanded "><a href="../modules/index.html">Pluggable Modules</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../modules/writing_a_module.html">Writing a module</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../modules/spam_checker_callbacks.html">Spam checker callbacks</a></li><li class="chapter-item expanded "><a href="../modules/third_party_rules_callbacks.html">Third-party rules callbacks</a></li><li class="chapter-item expanded "><a href="../modules/presence_router_callbacks.html">Presence router callbacks</a></li><li class="chapter-item expanded "><a href="../modules/account_validity_callbacks.html">Account validity callbacks</a></li><li class="chapter-item expanded "><a href="../modules/password_auth_provider_callbacks.html">Password auth provider callbacks</a></li><li class="chapter-item expanded "><a href="../modules/background_update_controller_callbacks.html">Background update controller callbacks</a></li><li class="chapter-item expanded "><a href="../modules/account_data_callbacks.html">Account data callbacks</a></li><li class="chapter-item expanded "><a href="../modules/porting_legacy_module.html">Porting a legacy module to the new interface</a></li></ol></li></ol></li><li class="chapter-item expanded "><a href="../workers.html">Workers</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../synctl_workers.html">Using synctl with Workers</a></li><li class="chapter-item expanded "><a href="../systemd-with-workers/index.html">Systemd</a></li></ol></li></ol></li><li class="chapter-item expanded "><a href="../usage/administration/index.html">Administration</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../usage/administration/admin_api/index.html">Admin API</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../admin_api/account_validity.html">Account Validity</a></li><li class="chapter-item expanded "><a href="../usage/administration/admin_api/background_updates.html">Background Updates</a></li><li class="chapter-item expanded "><a href="../admin_api/delete_group.html">Delete Group</a></li><li class="chapter-item expanded "><a href="../admin_api/event_reports.html">Event Reports</a></li><li class="chapter-item expanded "><a href="../admin_api/media_admin_api.html">Media</a></li><li class="chapter-item expanded "><a href="../admin_api/purge_history_api.html">Purge History</a></li><li class="chapter-item expanded "><a href="../admin_api/register_api.html">Register Users</a></li><li class="chapter-item expanded "><a href="../usage/administration/admin_api/registration_tokens.html">Registration Tokens</a></li><li class="chapter-item expanded "><a href="../admin_api/room_membership.html">Manipulate Room Membership</a></li><li class="chapter-item expanded "><a href="../admin_api/rooms.html">Rooms</a></li><li class="chapter-item expanded "><a href="../admin_api/server_notices.html">Server Notices</a></li><li class="chapter-item expanded "><a href="../admin_api/statistics.html">Statistics</a></li><li class="chapter-item expanded "><a href="../admin_api/user_admin_api.html">Users</a></li><li class="chapter-item expanded "><a href="../admin_api/version_api.html">Server Version</a></li><li class="chapter-item expanded "><a href="../usage/administration/admin_api/federation.html">Federation</a></li></ol></li><li class="chapter-item expanded "><a href="../manhole.html">Manhole</a></li><li class="chapter-item expanded "><a href="../metrics-howto.html">Monitoring</a></li><li class="chapter-item expanded "><a href="../usage/administration/understanding_synapse_through_grafana_graphs.html">Understanding Synapse Through Grafana Graphs</a></li><li class="chapter-item expanded "><a href="../usage/administration/useful_sql_for_admins.html">Useful SQL for Admins</a></li><li class="chapter-item expanded "><a href="../usage/administration/database_maintenance_tools.html">Database Maintenance Tools</a></li><li class="chapter-item expanded "><a href="../usage/administration/state_groups.html">State Groups</a></li><li class="chapter-item expanded "><a href="../usage/administration/request_log.html">Request log format</a></li><li class="chapter-item expanded "><a href="../usage/administration/admin_faq.html">Admin FAQ</a></li><li class="chapter-item expanded "><div>Scripts</div></li></ol></li><li class="chapter-item expanded "><li class="part-title">Development</li><li class="chapter-item expanded "><a href="../development/contributing_guide.html" class="active">Contributing Guide</a></li><li class="chapter-item expanded "><a href="../code_style.html">Code Style</a></li><li class="chapter-item expanded "><a href="../development/releases.html">Release Cycle</a></li><li class="chapter-item expanded "><a href="../development/git.html">Git Usage</a></li><li class="chapter-item expanded "><div>Testing</div></li><li><ol class="section"><li class="chapter-item expanded "><a href="../development/demo.html">Demo scripts</a></li></ol></li><li class="chapter-item expanded "><a href="../opentracing.html">OpenTracing</a></li><li class="chapter-item expanded "><a href="../development/database_schema.html">Database Schemas</a></li><li class="chapter-item expanded "><a href="../development/experimental_features.html">Experimental features</a></li><li class="chapter-item expanded "><div>Synapse Architecture</div></li><li><ol class="section"><li class="chapter-item expanded "><a href="../log_contexts.html">Log Contexts</a></li><li class="chapter-item expanded "><a href="../replication.html">Replication</a></li><li class="chapter-item expanded "><a href="../tcp_replication.html">TCP Replication</a></li></ol></li><li class="chapter-item expanded "><a href="../development/internal_documentation/index.html">Internal Documentation</a></li><li><ol class="section"><li class="chapter-item expanded "><div>Single Sign-On</div></li><li><ol class="section"><li class="chapter-item expanded "><a href="../development/saml.html">SAML</a></li><li class="chapter-item expanded "><a href="../development/cas.html">CAS</a></li></ol></li><li class="chapter-item expanded "><a href="../development/room-dag-concepts.html">Room DAG concepts</a></li><li class="chapter-item expanded "><div>State Resolution</div></li><li><ol class="section"><li class="chapter-item expanded "><a href="../auth_chain_difference_algorithm.html">The Auth Chain Difference Algorithm</a></li></ol></li><li class="chapter-item expanded "><a href="../media_repository.html">Media Repository</a></li><li class="chapter-item expanded "><a href="../room_and_user_statistics.html">Room and User Statistics</a></li></ol></li><li class="chapter-item expanded "><div>Scripts</div></li><li class="chapter-item expanded affix "><li class="part-title">Other</li><li class="chapter-item expanded "><a href="../deprecation_policy.html">Dependency Deprecation Policy</a></li><li class="chapter-item expanded "><a href="../other/running_synapse_on_single_board_computers.html">Running Synapse on a Single-Board Computer</a></li></ol>
+ <ol class="chapter"><li class="chapter-item expanded affix "><li class="part-title">Introduction</li><li class="chapter-item expanded "><a href="../welcome_and_overview.html">Welcome and Overview</a></li><li class="chapter-item expanded affix "><li class="part-title">Setup</li><li class="chapter-item expanded "><a href="../setup/installation.html">Installation</a></li><li class="chapter-item expanded "><a href="../postgres.html">Using Postgres</a></li><li class="chapter-item expanded "><a href="../reverse_proxy.html">Configuring a Reverse Proxy</a></li><li class="chapter-item expanded "><a href="../setup/forward_proxy.html">Configuring a Forward/Outbound Proxy</a></li><li class="chapter-item expanded "><a href="../turn-howto.html">Configuring a Turn Server</a></li><li class="chapter-item expanded "><a href="../delegate.html">Delegation</a></li><li class="chapter-item expanded affix "><li class="part-title">Upgrading</li><li class="chapter-item expanded "><a href="../upgrade.html">Upgrading between Synapse Versions</a></li><li class="chapter-item expanded affix "><li class="part-title">Usage</li><li class="chapter-item expanded "><a href="../federate.html">Federation</a></li><li class="chapter-item expanded "><a href="../usage/configuration/index.html">Configuration</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../usage/configuration/config_documentation.html">Configuration Manual</a></li><li class="chapter-item expanded "><a href="../usage/configuration/homeserver_sample_config.html">Homeserver Sample Config File</a></li><li class="chapter-item expanded "><a href="../usage/configuration/logging_sample_config.html">Logging Sample Config File</a></li><li class="chapter-item expanded "><a href="../structured_logging.html">Structured Logging</a></li><li class="chapter-item expanded "><a href="../templates.html">Templates</a></li><li class="chapter-item expanded "><a href="../usage/configuration/user_authentication/index.html">User Authentication</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../usage/configuration/user_authentication/single_sign_on/index.html">Single-Sign On</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../openid.html">OpenID Connect</a></li><li class="chapter-item expanded "><a href="../usage/configuration/user_authentication/single_sign_on/saml.html">SAML</a></li><li class="chapter-item expanded "><a href="../usage/configuration/user_authentication/single_sign_on/cas.html">CAS</a></li><li class="chapter-item expanded "><a href="../sso_mapping_providers.html">SSO Mapping Providers</a></li></ol></li><li class="chapter-item expanded "><a href="../password_auth_providers.html">Password Auth Providers</a></li><li class="chapter-item expanded "><a href="../jwt.html">JSON Web Tokens</a></li><li class="chapter-item expanded "><a href="../usage/configuration/user_authentication/refresh_tokens.html">Refresh Tokens</a></li></ol></li><li class="chapter-item expanded "><a href="../CAPTCHA_SETUP.html">Registration Captcha</a></li><li class="chapter-item expanded "><a href="../application_services.html">Application Services</a></li><li class="chapter-item expanded "><a href="../server_notices.html">Server Notices</a></li><li class="chapter-item expanded "><a href="../consent_tracking.html">Consent Tracking</a></li><li class="chapter-item expanded "><a href="../development/url_previews.html">URL Previews</a></li><li class="chapter-item expanded "><a href="../user_directory.html">User Directory</a></li><li class="chapter-item expanded "><a href="../message_retention_policies.html">Message Retention Policies</a></li><li class="chapter-item expanded "><a href="../modules/index.html">Pluggable Modules</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../modules/writing_a_module.html">Writing a module</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../modules/spam_checker_callbacks.html">Spam checker callbacks</a></li><li class="chapter-item expanded "><a href="../modules/third_party_rules_callbacks.html">Third-party rules callbacks</a></li><li class="chapter-item expanded "><a href="../modules/presence_router_callbacks.html">Presence router callbacks</a></li><li class="chapter-item expanded "><a href="../modules/account_validity_callbacks.html">Account validity callbacks</a></li><li class="chapter-item expanded "><a href="../modules/password_auth_provider_callbacks.html">Password auth provider callbacks</a></li><li class="chapter-item expanded "><a href="../modules/background_update_controller_callbacks.html">Background update controller callbacks</a></li><li class="chapter-item expanded "><a href="../modules/account_data_callbacks.html">Account data callbacks</a></li><li class="chapter-item expanded "><a href="../modules/porting_legacy_module.html">Porting a legacy module to the new interface</a></li></ol></li></ol></li><li class="chapter-item expanded "><a href="../workers.html">Workers</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../synctl_workers.html">Using synctl with Workers</a></li><li class="chapter-item expanded "><a href="../systemd-with-workers/index.html">Systemd</a></li></ol></li></ol></li><li class="chapter-item expanded "><a href="../usage/administration/index.html">Administration</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../usage/administration/admin_api/index.html">Admin API</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../admin_api/account_validity.html">Account Validity</a></li><li class="chapter-item expanded "><a href="../usage/administration/admin_api/background_updates.html">Background Updates</a></li><li class="chapter-item expanded "><a href="../admin_api/delete_group.html">Delete Group</a></li><li class="chapter-item expanded "><a href="../admin_api/event_reports.html">Event Reports</a></li><li class="chapter-item expanded "><a href="../admin_api/media_admin_api.html">Media</a></li><li class="chapter-item expanded "><a href="../admin_api/purge_history_api.html">Purge History</a></li><li class="chapter-item expanded "><a href="../admin_api/register_api.html">Register Users</a></li><li class="chapter-item expanded "><a href="../usage/administration/admin_api/registration_tokens.html">Registration Tokens</a></li><li class="chapter-item expanded "><a href="../admin_api/room_membership.html">Manipulate Room Membership</a></li><li class="chapter-item expanded "><a href="../admin_api/rooms.html">Rooms</a></li><li class="chapter-item expanded "><a href="../admin_api/server_notices.html">Server Notices</a></li><li class="chapter-item expanded "><a href="../admin_api/statistics.html">Statistics</a></li><li class="chapter-item expanded "><a href="../admin_api/user_admin_api.html">Users</a></li><li class="chapter-item expanded "><a href="../admin_api/version_api.html">Server Version</a></li><li class="chapter-item expanded "><a href="../usage/administration/admin_api/federation.html">Federation</a></li></ol></li><li class="chapter-item expanded "><a href="../manhole.html">Manhole</a></li><li class="chapter-item expanded "><a href="../metrics-howto.html">Monitoring</a></li><li class="chapter-item expanded "><a href="../usage/administration/understanding_synapse_through_grafana_graphs.html">Understanding Synapse Through Grafana Graphs</a></li><li class="chapter-item expanded "><a href="../usage/administration/useful_sql_for_admins.html">Useful SQL for Admins</a></li><li class="chapter-item expanded "><a href="../usage/administration/database_maintenance_tools.html">Database Maintenance Tools</a></li><li class="chapter-item expanded "><a href="../usage/administration/state_groups.html">State Groups</a></li><li class="chapter-item expanded "><a href="../usage/administration/request_log.html">Request log format</a></li><li class="chapter-item expanded "><a href="../usage/administration/admin_faq.html">Admin FAQ</a></li><li class="chapter-item expanded "><div>Scripts</div></li></ol></li><li class="chapter-item expanded "><li class="part-title">Development</li><li class="chapter-item expanded "><a href="../development/contributing_guide.html" class="active">Contributing Guide</a></li><li class="chapter-item expanded "><a href="../code_style.html">Code Style</a></li><li class="chapter-item expanded "><a href="../development/releases.html">Release Cycle</a></li><li class="chapter-item expanded "><a href="../development/git.html">Git Usage</a></li><li class="chapter-item expanded "><div>Testing</div></li><li><ol class="section"><li class="chapter-item expanded "><a href="../development/demo.html">Demo scripts</a></li></ol></li><li class="chapter-item expanded "><a href="../opentracing.html">OpenTracing</a></li><li class="chapter-item expanded "><a href="../development/database_schema.html">Database Schemas</a></li><li class="chapter-item expanded "><a href="../development/experimental_features.html">Experimental features</a></li><li class="chapter-item expanded "><div>Synapse Architecture</div></li><li><ol class="section"><li class="chapter-item expanded "><a href="../development/synapse_architecture/cancellation.html">Cancellation</a></li><li class="chapter-item expanded "><a href="../log_contexts.html">Log Contexts</a></li><li class="chapter-item expanded "><a href="../replication.html">Replication</a></li><li class="chapter-item expanded "><a href="../tcp_replication.html">TCP Replication</a></li></ol></li><li class="chapter-item expanded "><a href="../development/internal_documentation/index.html">Internal Documentation</a></li><li><ol class="section"><li class="chapter-item expanded "><div>Single Sign-On</div></li><li><ol class="section"><li class="chapter-item expanded "><a href="../development/saml.html">SAML</a></li><li class="chapter-item expanded "><a href="../development/cas.html">CAS</a></li></ol></li><li class="chapter-item expanded "><a href="../development/room-dag-concepts.html">Room DAG concepts</a></li><li class="chapter-item expanded "><div>State Resolution</div></li><li><ol class="section"><li class="chapter-item expanded "><a href="../auth_chain_difference_algorithm.html">The Auth Chain Difference Algorithm</a></li></ol></li><li class="chapter-item expanded "><a href="../media_repository.html">Media Repository</a></li><li class="chapter-item expanded "><a href="../room_and_user_statistics.html">Room and User Statistics</a></li></ol></li><li class="chapter-item expanded "><div>Scripts</div></li><li class="chapter-item expanded affix "><li class="part-title">Other</li><li class="chapter-item expanded "><a href="../deprecation_policy.html">Dependency Deprecation Policy</a></li><li class="chapter-item expanded "><a href="../other/running_synapse_on_single_board_computers.html">Running Synapse on a Single-Board Computer</a></li></ol>
</div>
<div id="sidebar-resize-handle" class="sidebar-resize-handle"></div>
</nav>
@@ -279,7 +279,20 @@ in production (and indeed, we have some code paths specific to each database).
This means that we need to run our unit tests against PostgreSQL too. Our CI does
this automatically for pull requests and release candidates, but it's sometimes
useful to reproduce this locally.</p>
-<p>To do so, <a href="../postgres.html">configure Postgres</a> and run <code>trial</code> with the
+<h4 id="using-docker"><a class="header" href="#using-docker">Using Docker</a></h4>
+<p>The easiest way to do so is to run Postgres via a docker container. In one
+terminal:</p>
+<pre><code class="language-shell">docker run --rm -e POSTGRES_PASSWORD=mysecretpassword -e POSTGRES_USER=postgres -e POSTGRES_DB=postgress -p 5432:5432 postgres:14
+</code></pre>
+<p>If you see an error like</p>
+<pre><code>docker: Error response from daemon: driver failed programming external connectivity on endpoint nice_ride (b57bbe2e251b70015518d00c9981e8cb8346b5c785250341a6c53e3c899875f1): Error starting userland proxy: listen tcp4 0.0.0.0:5432: bind: address already in use.
+</code></pre>
+<p>then something is already bound to port 5432. You're probably already running postgres locally.</p>
+<p>Once you have a postgres server running, invoke <code>trial</code> in a second terminal:</p>
+<pre><code class="language-shell">SYNAPSE_POSTGRES=1 SYNAPSE_POSTGRES_HOST=127.0.0.1 SYNAPSE_POSTGRES_USER=postgres SYNAPSE_POSTGRES_PASSWORD=mysecretpassword poetry run trial tests
+</code></pre>
+<h4 id="using-an-existing-postgres-installation"><a class="header" href="#using-an-existing-postgres-installation">Using an existing Postgres installation</a></h4>
+<p>If you have postgres already installed on your system, you can run <code>trial</code> with the
following environment variables matching your configuration:</p>
<ul>
<li><code>SYNAPSE_POSTGRES</code> to anything nonempty</li>
@@ -298,7 +311,8 @@ trial
<p>You don't need to specify the host, user, port or password if your Postgres
server is set to authenticate you over the UNIX socket (i.e. if the <code>psql</code> command
works without further arguments).</p>
-<p>Your Postgres account needs to be able to create databases.</p>
+<p>Your Postgres account needs to be able to create databases; see the postgres
+docs for <a href="https://www.postgresql.org/docs/current/sql-alterrole.html"><code>ALTER ROLE</code></a>.</p>
<h2 id="run-the-integration-tests-sytest"><a class="header" href="#run-the-integration-tests-sytest">Run the integration tests (<a href="https://github.com/matrix-org/sytest">Sytest</a>).</a></h2>
<p>The integration tests are a more comprehensive suite of tests. They
run a full version of Synapse, including your changes, to check if
@@ -424,8 +438,8 @@ and you agree to license it under the same terms as the project's license, we've
same lightweight approach that the Linux Kernel
<a href="https://www.kernel.org/doc/html/latest/process/submitting-patches.html#sign-your-work-the-developer-s-certificate-of-origin%3E">submitting patches process</a>,
<a href="https://github.com/docker/docker/blob/master/CONTRIBUTING.md">Docker</a>, and many other
-projects use: the DCO (Developer Certificate of Origin:
-http://developercertificate.org/). This is a simple declaration that you wrote
+projects use: the DCO (<a href="http://developercertificate.org/">Developer Certificate of Origin</a>).
+This is a simple declaration that you wrote
the contribution or otherwise have the right to contribute it to Matrix:</p>
<pre><code>Developer Certificate of Origin
Version 1.1
|
