Melya is a framework for Google App Engine (GAE) that allows you to build websites using CoffeeScript, JavaScript, HTML, and Python.
Documentation can be found here
Your Python, CoffeeScript, JavaScript, and HTML can all be edited online.
So you can now build and edit your GAE website from anywhere, and see the changes instantly (without deploying).
Support for multiple domains.
Framework helps you modularize your code.
Javascript packing of multiple modules in one, for fast page loads.
Edit your site online, but still have your users see the stable version. Push updates to everyone only when you want.
Basic GitHub integration (coming soon). Push and pull changes.
And much more...