diff --git a/modern_di_faststream/main.py b/modern_di_faststream/main.py
index 72c4f82..5fa3a2e 100644
--- a/modern_di_faststream/main.py
+++ b/modern_di_faststream/main.py
@@ -15,6 +15,12 @@
 
 faststream_message_provider = providers.ContextProvider(scope=Scope.REQUEST, context_type=faststream.StreamMessage)
 
+# Keys under which the containers live in FastStream's ``ContextRepo``. Each is
+# written in one place and read in another; naming them keeps writer and reader
+# in provable agreement instead of relying on two matching string literals.
+_ROOT_CONTAINER_KEY = "di_container"
+_REQUEST_CONTAINER_KEY = "request_container"
+
 
 class _DIMiddlewareFactory:
     __slots__ = ("di_container",)
@@ -41,7 +47,7 @@ async def consume_scope(
             scope=modern_di.Scope.REQUEST, context={faststream.StreamMessage: msg}
         )
         try:
-            with self.context.scope("request_container", request_container):
+            with self.context.scope(_REQUEST_CONTAINER_KEY, request_container):
                 return typing.cast(
                     typing.AsyncIterator[DecodedMessage],
                     await call_next(msg),
@@ -51,7 +57,7 @@ async def consume_scope(
 
 
 def fetch_di_container(app_: faststream.FastStream | AsgiFastStream) -> Container:
-    return typing.cast(Container, app_.context.get("di_container"))
+    return typing.cast(Container, app_.context.get(_ROOT_CONTAINER_KEY))
 
 
 def setup_di(
@@ -63,7 +69,7 @@ def setup_di(
         raise RuntimeError(msg)
 
     container.providers_registry.add_providers(faststream_message_provider)
-    app.context.set_global("di_container", container)
+    app.context.set_global(_ROOT_CONTAINER_KEY, container)
     # FastStream's lifecycle is callback-based, so the root container can't be
     # wrapped in ``async with``. Reopen it on startup (before the broker consumes)
     # to pair with the shutdown close, so a broker restart works instead of
@@ -80,7 +86,7 @@ class Dependency(typing.Generic[T_co]):
     dependency: providers.AbstractProvider[T_co] | type[T_co]
 
     async def __call__(self, context: faststream.ContextRepo) -> T_co:
-        request_container: Container = context.get("request_container")
+        request_container: Container = context.get(_REQUEST_CONTAINER_KEY)
         if isinstance(self.dependency, providers.AbstractProvider):
             return request_container.resolve_provider(self.dependency)
         return request_container.resolve(dependency_type=self.dependency)