libTiMidity is a MIDI to WAVE converter library that uses Gravis Ultrasound-compatible patch files to generate digital audio data from General MIDI files. This library based on the TiMidity decoder from SDL_sound library.
ASDRAD is a source code generator which reads a configuration file and generates *.c, *.h, makefiles etc. It's written in Python and uses templates. Output files are for AmigaOS and derivates like AROS and MorphOS.
Cross-platform reimplementation of AMOS BASIC (runtime)
XAMOS is a cross-platform reimplementation of AMOS BASIC based on jAMOS, fully re-written in C++ with SDL libraries.
Currently runtime only, however is widely compatible with jAMOS projects.