Comment by gozo

I guess you can either see it as how much faster Cowboy is or how much more useful Rails is. It's nice if you have a lot of Erlang code already, but if you're making a web application from scratch, performance is pretty far down the list and I would stick to the half dozen stacks that are proven. Erlang can make sense sometimes, but it's probably not(!) comparable to Rails in those cases.

Edit: Eh, I forgot a "not" in the last sentence, which is now added.