diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index d435c30..361cd16 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -45,7 +45,7 @@ repos:
     -   id: reorder-python-imports
 
 -   repo: https://github.com/pre-commit/mirrors-mypy
-    rev: 'v1.4.1'
+    rev: 'v1.5.1'
     hooks:
     -   id: mypy
         args:
diff --git a/ahk/message.py b/ahk/message.py
index b6a59df..be10359 100644
--- a/ahk/message.py
+++ b/ahk/message.py
@@ -143,8 +143,7 @@ def unpack(self) -> Any:
         return NotImplemented
 
 
-_message_registry: dict[bytes, 'ResponseMessageClassTypes']
-_message_registry = {ResponseMessage._type_order_mark: ResponseMessage}
+_message_registry: dict[bytes, 'ResponseMessageClassTypes'] = {}
 
 
 class TupleResponseMessage(ResponseMessage):