diff --git a/packages/celery-library/tests/conftest.py b/packages/celery-library/tests/conftest.py
index 5ecde6333f9..4d37e3a4e6d 100644
--- a/packages/celery-library/tests/conftest.py
+++ b/packages/celery-library/tests/conftest.py
@@ -32,7 +32,8 @@
 
 class FakeAppServer(BaseAppServer):
     async def lifespan(self, startup_completed_event: threading.Event) -> None:
-        pass
+        startup_completed_event.set()
+        await self.shutdown_event.wait()  # wait for shutdown
 
 
 @pytest.fixture