I try whenever possible to release my game code and development tools as open source. In addition to the source links on the game pages on this site, I have released several standalone codebases:
- Jumpcore, based on the code from “Jumpman” and “iJumpman” and used for “Drumcircle”. This is a simple C/C++ framework noteworthy mostly for working out of the box on Mac, Windows, Linux, iOS, Android and WebOS.
- Polyconsole, a wrapper on Polycode allowing one to write PC games in a mixture of C++ and Lua.
- Emily, a programming language meant to feel like scripting languages like Python or Lua but conceptually resemble functional languages like ML. (You can write games in it, but the current version is a little slow.)
All three of the above are available under the permissive “MIT” license. All of the games on this site meanwhile have source code included on their respective pages; these usually are under a “free for any noncommercial use” creative commons license.
My Polycode-based games have a built-in modding architecture. You can find a guide to using that here.