An empty starting point for a stateless Ruby API using the rails-api gem, with a React client side app. To fit the definition of stateless, the API does not include action-view, sprockets, or sessions. Roughly speaking, React replaces action-view, Webpack replaces sprockets, and JWT replaces sessions.
There's a detailed tutorial on how to build this project at: http://fredguest.com/2015/03/06/building-a-stateless-rails-api-with-react-and-twitter-oauth/
There's a live demo of the finished project at: https://blabs.herokuapp.com