`deriveGEq` for multiindex GADTs?

[srid]

How would one use deriveGEq to automatically derive this type?

data Response resp a where
  Response_Loading :: Response resp ()
  Response_BadResponse :: Response resp ()
  Response_BackendError :: Response resp AppError
  Response_Available :: Response resp resp

instance GEq (Response resp) where
  geq Response_Loading Response_Loading = Just Refl
  geq Response_BadResponse Response_BadResponse = Just Refl
  geq Response_BackendError Response_BackendError = Just Refl
  geq Response_Available Response_Available = Just Refl
  geq _ _ = Nothing