diff --git a/taskiq/brokers/inmemory_broker.py b/taskiq/brokers/inmemory_broker.py
index 23d64ef..c2262b1 100644
--- a/taskiq/brokers/inmemory_broker.py
+++ b/taskiq/brokers/inmemory_broker.py
@@ -130,7 +130,7 @@ def __init__(
         await_inplace: bool = False,
     ) -> None:
         super().__init__()
-        self.result_backend = InmemoryResultBackend(
+        self.result_backend: InmemoryResultBackend[Any] = InmemoryResultBackend(
             max_stored_results=max_stored_results,
         )
         self.executor = ThreadPoolExecutor(sync_tasks_pool_size)