diff --git a/packages/testing/src/consensus_testing/pytest_plugins/filler.py b/packages/testing/src/consensus_testing/pytest_plugins/filler.py
index aa44339b2..4953b59e8 100644
--- a/packages/testing/src/consensus_testing/pytest_plugins/filler.py
+++ b/packages/testing/src/consensus_testing/pytest_plugins/filler.py
@@ -97,7 +97,7 @@ def write_fixtures(self) -> None:
                 test_id = f"{test_nodeid}[fork_{self.fork}-{fixture_format}]"
                 all_tests[test_id] = fixture.json_dict_with_info()
 
-            with open(output_file, "w") as output_handle:
+            with output_file.open("w") as output_handle:
                 json.dump(all_tests, output_handle, indent=4)