In the past two days I've learned a lot about how you can extend OpenToonz/Tahoma2D. I started off thinking it's primarily in C++ with OpenCV, but you can also extend it with themes in CSS, GLSL shaders, particle effects, user macros to set presets for convenience, MyPaint brushes, and other stuff I might not have even discovered yet. I'll keep making news posts to this as I toy with it.
I made this because I wanted to help contribute to opentoonz as well as add additional documentation I found to be lacking. It's been one hell of a ride, but I think it's paying off so far. I at first posted it in my file dump, but it's gotten big enough to justify a github repository. OpenToonz/Tahoma2D is incredibly powerful, it just needs more contributions and documentations for others to be inspired to make their own.