diff --git a/ryven-editor/ryven/main/packages/gui_env.py b/ryven-editor/ryven/main/packages/gui_env.py
index 24ee2d5d..a46866a3 100644
--- a/ryven-editor/ryven/main/packages/gui_env.py
+++ b/ryven-editor/ryven/main/packages/gui_env.py
@@ -56,7 +56,7 @@ def register_gui(gui_cls: Type[NodeGUI]):
             assert hasattr(node_cls, 'GUI')
             InfoMsgs.write(f'{node_cls.__name__} has defined an explicit gui {node_cls.GUI.__name__}')
             return
-        node_cls.GUI = gui_cls
+        node_cls.GUI = gui_cls  # type: ignore
         __explicit_nodes.add(node_cls)
         InfoMsgs.write(f"Registered node gui: {gui_cls} for {node_cls}")
         return gui_cls