1 files changed, 3 insertions, 3 deletions
diff --git a/mypy.ini b/mypy.ini
index 5e7057cfb7..a7ec66196d 100644
--- a/mypy.ini
+++ b/mypy.ini
@@ -13,6 +13,9 @@ no_implicit_optional = True
 disallow_untyped_defs = True
 strict_equality = True
 warn_redundant_casts = True
+# Run mypy type checking with the minimum supported Python version to catch new usage
+# that isn't backwards-compatible (types, overloads, etc).
+python_version = 3.8
 
 files =
   docker/,
@@ -29,9 +32,6 @@ warn_unused_ignores = False
 [mypy-synapse.util.caches.treecache]
 disallow_untyped_defs = False
 
-[mypy-tests.util.caches.test_descriptors]
-disallow_untyped_defs = False
-
 ;; Dependencies without annotations
 ;; Before ignoring a module, check to see if type stubs are available.
 ;; The `typeshed` project maintains stubs here: