Great question. We have loads of Sinatra services running on CoreOS (using Fleet and Git for deploys) http://blog.clearbit.com/servers-part-one http://blog.clea

Great question. We have loads of Sinatra services running on CoreOS (using Fleet and Git for deploys) http://blog.clearbit.com/servers-part-one http://blog.clearbit.com/servers-part-one. From there we have a contrib Gem to share middleware between the services. These middlewares handle Auth, Rate limiting, CORS, etc.