Scalatra is one of a new breed of simple, accessible, scalable web frameworks. It combines the power of the JVM with the beauty and brevity of Scala, allowing you to build high-performance web APIs which may be asynchronous or realtime.
It's used in production by LinkedIn, the Guardian newspaper
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, games website IGN, and the UK government. It's also a great server-side counterpart to client-side development frameworks such as backbone.js or angular.js. [Less]