Strange that there's no mention of Rails new/potential "API only" mode: https://github.com/rails/rails/blob/efd557a60cd976ac17be9e23...

This will make it much easier to only use Rails as an API and get rid of a lot of the bloat/complexity people seem to complain about.

This was posted on edgeguides but it's since been removed some reason (http://edgeguides.rubyonrails.org/api_app.html).