for specifics, would recommend to simply read the code. for overall context, geohot has done interviews ([0], [1]) and that give overview of comma/openpilot at high level.

[0] http://www.autonocast.com/blog/2018/7/13/91-hotz-takes-with-... [1] https://youtu.be/iwcYp-XT7UI?t=1605