Hey, I just tried to use the library but unfortunately there is no type check in .case method for return value.

If I implement my reducer like this:

const execute = (execute: Execute, action: ReduxAction): Execute => {  if (isType(action, actions.calibrationSettingsDone)) return { ...execute, settings: action.payload.result };...

it will not allow me to return settings1 property because it doesn't exist in Execute model and it's fine however in your library it's completely fine to return any object.