1 files changed, 5 insertions, 8 deletions
diff --git a/synapse/python_dependencies.py b/synapse/python_dependencies.py
index aab77fc453..c899ca14d3 100644
--- a/synapse/python_dependencies.py
+++ b/synapse/python_dependencies.py
@@ -40,6 +40,10 @@ logger = logging.getLogger(__name__)
 # Note that these both represent runtime dependencies (and the versions
 # installed are checked at runtime).
 #
+# Also note that we replicate these constraints in the Synapse Dockerfile while
+# pre-installing dependencies. If these constraints are updated here, the same
+# change should be made in the Dockerfile.
+#
 # [1] https://pip.pypa.io/en/stable/reference/pip_install/#requirement-specifiers.
 
 REQUIREMENTS = [
@@ -69,14 +73,7 @@ REQUIREMENTS = [
     "msgpack>=0.5.2",
     "phonenumbers>=8.2.0",
     # we use GaugeHistogramMetric, which was added in prom-client 0.4.0.
-    # prom-client has a history of breaking backwards compatibility between
-    # minor versions (https://github.com/prometheus/client_python/issues/317),
-    # so we also pin the minor version.
-    #
-    # Note that we replicate these constraints in the Synapse Dockerfile while
-    # pre-installing dependencies. If these constraints are updated here, the
-    # same change should be made in the Dockerfile.
-    "prometheus_client>=0.4.0,<0.9.0",
+    "prometheus_client>=0.4.0",
     # we use attr.validators.deep_iterable, which arrived in 19.1.0 (Note:
     # Fedora 31 only has 19.1, so if we want to upgrade we should wait until 33
     # is out in November.)