... it turns out extracting Aura.Dispatcher was the key to reducing the Aura.Web package contents. With Aura.Dispatcher, any object can be a controller, since it can dispatch to any method on any object (as well as dispatching to closures). In turn, there is no more need for the Aura.Web package to provide a base controller with interfaces for various implementations. Instead, you can dispatch to any object you like, with the dependencies you prefer, as your controller. That controller object can be implemented at the framework level, or in a separate package or bundle.

As a result, this means that web-specific request and response objects can be in their own package independent of any particular controller implementation. The Aura.Web v2 package contains only those request and response objects.

via A Peek At Aura v2 -- Aura.Web.

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