Cocos2D-XNA is a 2D/3D game developer’s framework that is written specifically for XNA. XNA is the game API developed by Microsoft for independently published games on Xbox Live Arcade. To support other platforms than the now deprecated Microsoft XNA targets, Cocos2D-XNA supports the MonoGame runtime.
This project is open source, freely available, and free of royalties or encumberance. The software is released under the highly permissive MIT License.
The source code is hosted at github: https://github.com/Cocos2DXNA/cocos2d-xna