diff --git a/pkgs/development/python-modules/pysnooz/default.nix b/pkgs/development/python-modules/pysnooz/default.nix
index 7cf1205ed396..18662b42c4dd 100644
--- a/pkgs/development/python-modules/pysnooz/default.nix
+++ b/pkgs/development/python-modules/pysnooz/default.nix
@@ -5,6 +5,7 @@
 , buildPythonPackage
 , events
 , fetchFromGitHub
+, fetchpatch
 , freezegun
 , home-assistant-bluetooth
 , poetry-core
@@ -29,6 +30,16 @@ buildPythonPackage rec {
     hash = "sha256-K99sE9vxJo6grkp04DmTKOVqdfpQI0kUzJjSR6gnSew=";
   };
 
+  patches = [
+    (fetchpatch {
+      # fix tests against bleak 0.20.0+
+      # https://github.com/AustinBrunkhorst/pysnooz/pull/9
+      name = "pysnooz-bleak-0.20.0-compat.patch";
+      url = "https://github.com/AustinBrunkhorst/pysnooz/commit/594951051ceb40003975e61d64cfc683188d87d3.patch";
+      hash = "sha256-cWQt9V9IOB0YoW5zUR0PBTqS0a30fMTHpXH6CxWKRcc=";
+    })
+  ];
+
   postPatch = ''
     substituteInPlace pyproject.toml \
       --replace 'transitions = "^0.8.11"' 'transitions = ">0.8.11"' \