There is no offical repository there the development is going. The source code is released irregularly and placed at the http://www.pragma-ade.com website. The git and source browser repositories are updated by a script from the Current and Beta versions of the source code.
- Inside ConTeXt: Macros, commands, and other programming.
- MK IV implementation reports
- LuaTeX documentation
- Documentation of the source code
- The Release Notes page documents what has changed in each new release