I don't know, I have never mixed middleware from different libraries even using python - I always used Django, or Flask, or Bottle on their own. The existence of a basic HTTP server in the standard library can be used as a common ground on which one can develop frameworks (this is what Rosencrantz does), but then there are standalone projects such as [HTTPBeast](https://github.com/dom96/httpbeast) or [Mofuw](https://github.com/2vg/mofuw) (now archived).
One thing I wanted to do is abstracting the notion of handler in order to be able to support both the stdlib server AND HTTPBeast, but I could not find the time for this yet
