diff --git a/packages/modern-di-faststream/tests_faststream/dependencies.py b/packages/modern-di-faststream/tests_faststream/dependencies.py
index ce2ee97..0a78d17 100644
--- a/packages/modern-di-faststream/tests_faststream/dependencies.py
+++ b/packages/modern-di-faststream/tests_faststream/dependencies.py
@@ -15,8 +15,8 @@ class DependentCreator:
     dep1: SimpleCreator
 
 
-def fetch_message_is_processed_from_request(message: StreamMessage[typing.Any]) -> bool:
-    return message.processed
+def fetch_message_is_processed_from_request(message: StreamMessage[typing.Any] | None = None) -> bool:
+    return message.processed if message else False
 
 
 class Dependencies(Group):
diff --git a/packages/modern-di-litestar/tests_litestar/dependencies.py b/packages/modern-di-litestar/tests_litestar/dependencies.py
index a503cfd..e40352d 100644
--- a/packages/modern-di-litestar/tests_litestar/dependencies.py
+++ b/packages/modern-di-litestar/tests_litestar/dependencies.py
@@ -15,12 +15,12 @@ class DependentCreator:
     dep1: SimpleCreator
 
 
-def fetch_method_from_request(request: litestar.Request[typing.Any, typing.Any, typing.Any]) -> str:
+def fetch_method_from_request(request: litestar.Request[typing.Any, typing.Any, typing.Any] | None = None) -> str:
     assert isinstance(request, litestar.Request)
     return request.method
 
 
-def fetch_url_from_websocket(websocket: litestar.WebSocket[typing.Any, typing.Any, typing.Any]) -> str:
+def fetch_url_from_websocket(websocket: litestar.WebSocket[typing.Any, typing.Any, typing.Any] | None = None) -> str:
     assert isinstance(websocket, litestar.WebSocket)
     return websocket.url.path
 
diff --git a/packages/modern-di/modern_di/types_parser.py b/packages/modern-di/modern_di/types_parser.py
index 83df6c4..9bdfd91 100644
--- a/packages/modern-di/modern_di/types_parser.py
+++ b/packages/modern-di/modern_di/types_parser.py
@@ -14,29 +14,40 @@ class SignatureItem:
     default: object = UNSET
 
     @classmethod
-    def from_type(cls, type_: type, default: object = UNSET) -> "SignatureItem":
+    def from_type(cls, type_: type, default: object = UNSET) -> "SignatureItem":  # noqa: C901
         if type_ is types.NoneType:
             return cls()
 
+        # typing.Annotated
         if isinstance(type_, typing._AnnotatedAlias):  # type: ignore[attr-defined]  # noqa: SLF001
             type_ = type_.__args__[0]
 
         result: dict[str, typing.Any] = {"default": default}
+
+        # union type
         if isinstance(type_, (types.UnionType, typing._UnionGenericAlias)):  # type: ignore[attr-defined]  # noqa: SLF001
             args = [x.__origin__ if isinstance(x, types.GenericAlias) else x for x in type_.__args__]
             if types.NoneType in args:
                 result["is_nullable"] = True
                 args.remove(types.NoneType)
+
+            for i, arg in enumerate(args):
+                if isinstance(arg, (types.GenericAlias, typing._GenericAlias)):  # type: ignore[attr-defined]  # noqa: SLF001
+                    args[i] = arg.__origin__
+
             if len(args) > 1:
                 result["args"] = args
             elif args:
                 result["arg_type"] = args[0]
+
+        # generic
         elif isinstance(type_, (types.GenericAlias, typing._GenericAlias)):  # type: ignore[attr-defined]  # noqa: SLF001
             result["arg_type"] = type_.__origin__
             result["args"] = list(type_.__args__)
 
         elif isinstance(type_, type):
             result["arg_type"] = type_
+
         return cls(**result)
 
 
diff --git a/packages/modern-di/tests_core/test_types_parser.py b/packages/modern-di/tests_core/test_types_parser.py
index a40be7a..733dc44 100644
--- a/packages/modern-di/tests_core/test_types_parser.py
+++ b/packages/modern-di/tests_core/test_types_parser.py
@@ -22,6 +22,7 @@ class GenericClass(typing.Generic[types.T]): ...
         (typing.Union[str | int], SignatureItem(args=[str, int])),  # noqa: UP007
         (list[str] | None, SignatureItem(arg_type=list, is_nullable=True)),
         (GenericClass[str], SignatureItem(arg_type=GenericClass, args=[str])),
+        (GenericClass[str] | None, SignatureItem(arg_type=GenericClass, is_nullable=True)),
     ],
 )
 def test_signature_item_parser(type_: type, result: SignatureItem) -> None: