Controller
in package
This class just ensures that applications have controllers that are explicitly designed to be served publicly. If your controller does not extend this class, Spitfire will deny access to any requests headed it's way.
While this is not technically required with the new Routers, it provides a good level of enforcement to explicitly declare publicly served content, since otherwise.
Currently, the controllers provide no methods, this means that your application can use any methods for itself. Future revisions may include a property that provides utils for your controller.
Please note that you should avoid routing any requests to methods starting with an underscore (except for the magic __invoke method)