Borland's Object Windows Library for the modern age
Source code is here - https://sourceforge.net/projects/lcmd-git/
ESP8266 framework for Homie, a lightweight MQTT convention
Keystone assembler framework: Core (Arm, Arm64, Hexagon, Mips, etc.)
State machine framework for reactive embedded systems
The official mirror of the V8 Git repository
Simple graphics, keyboard and mouse library with a C interface