diff --git a/tests/conftest.py b/tests/conftest.py
index 1a55a45..293f0f2 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -9,6 +9,6 @@
 @pytest.fixture
 def app() -> web.Application:
     application = web.Application()
-    container = modern_di.Container(groups=[Dependencies])
+    container = modern_di.Container(groups=[Dependencies], validate=True)
     setup_di(application, container)
     return application
diff --git a/tests/test_lifespan.py b/tests/test_lifespan.py
index a392fb8..91fc36b 100644
--- a/tests/test_lifespan.py
+++ b/tests/test_lifespan.py
@@ -18,7 +18,7 @@ async def _ok(request: web.Request) -> web.Response:  # noqa: ARG001
 
 
 async def test_startup_reopens_closed_root(aiohttp_client: AiohttpClient) -> None:
-    container = modern_di.Container(groups=[Dependencies])
+    container = modern_di.Container(groups=[Dependencies], validate=True)
     container.close_sync()
     assert container.closed
 
@@ -34,7 +34,7 @@ async def test_startup_reopens_closed_root(aiohttp_client: AiohttpClient) -> Non
 
 async def test_cleanup_closes_root() -> None:
     app = web.Application()
-    container = modern_di.Container(groups=[Dependencies])
+    container = modern_di.Container(groups=[Dependencies], validate=True)
     setup_di(app, container)
 
     await _on_startup(app)