As I understand, the asyncio module was inspired by Twisted.

Growler is, at its heart, a super minimal interface: passing (req, res) pairs through a pipeline of middleware (similar to node).

Since this is built with the standard library, all kinds of features, such as async DB access, will become available as the community builds them; and these may be added to your pipeline super cheap.

It's just an experiment.

It's asyncio native. Also I think syntactically it's different.