I assume that http2 won't come with 2.0 . Still, I'd like to know where we stand, what's missing for rack to develop further in that direction and where could I help/contribute. Hopefully there's a document someone can redirect me to. 

I'm really looking forward to hearing from someone, possibly Mr. Patterson, who's clearly been working in this. I think ruby needs http2 badly. I think that all other standards for pushing server-to-client/full-duplex/pipe-in-my-json will die after widespread adoption, like image spriting and all those HTTP1 performance "enhancements". I think that the ruby frameworks don't need and should not enforce websockets, specially for thing it was not designed for. I think ActionCable is crap. And just as Rails, I am entitled to an opinion, and would like to try to force it into people's throats. And I'd like to force http2 and consider myself a better human being after that.

Only thing I found was this: https://groups.google.com/forum/#!topic/rack-devel/lipvWVZrcfo and after the author left the project. What's the status?

Really appreciate any feedback,
Tiago