Raptor is a radically new Ruby web server, built for two goals:
performance and visbility.
Raptor has an innovative and optimized HTTP engine, making it up to 4x
faster than Unicorn, up to 2x faster than Puma and up to 2x faster than
Torquebox.
Raptor gives you visibility into your app’s behavior, so that you can
easily analyze problems. No more pulling your hair out during
production, wondering why the app is misbehaving.
You can learn more at: http://www.rubyraptor.org/