diff --git a/pkgs/development/python-modules/discovery30303/default.nix b/pkgs/development/python-modules/discovery30303/default.nix
index 49de32439d12..c9b09cbfe69c 100644
--- a/pkgs/development/python-modules/discovery30303/default.nix
+++ b/pkgs/development/python-modules/discovery30303/default.nix
@@ -31,6 +31,10 @@ buildPythonPackage rec {
     pytestCheckHook
   ];
 
+  pytestFlagsArray = [
+    "--asyncio-mode=legacy"
+  ];
+
   postPatch = ''
     substituteInPlace pyproject.toml \
       --replace " --cov=discovery30303" ""