I’ve been thinking about PSR-7 from PHP-FIG. In most MVC frameworks the request/response objects act like a pipeline. And there are many reasons this won’t work in WP on the response side – the REST API has a specific response object and conventional PHP templated themes are emitting markup rather than building an object to echo.
But, I still like having a request object. I want to explore that more.
A recent use case was building a mu-plugins image proxy.