See PHP-SG/sr-2
There are many benefits that App level standardization provides:
- Tool builders can build without need to know specific implementations
- Implementors of tools can choose any tool that conforms to the standard
- Programmers have an expected interface to the App that allows less time looking up how to do things in a framework and more time on doing things
At present, SR-2 provides for a standard for layering. This layering allows for the normal middleware model, but also allows for the model of before and after, as Symfony does with kernel events.
It is intended this standard will expand to include container access and events.