athenaCL

http://www.flexatone.net/athena.html

modular, polyphonic, poly-paradigm algorithmic music composition in a cross-platform interactive command-line environment.

The athenaCL system is an open-source, object-oriented composition tool written in Python. The system can be scripted and embedded, and includes integrated instrument libraries, post-tonal and microtonal pitch modeling tools, multiple-format graphical outputs, and musical output in Csound, MIDI, audio file, XML, and text formats.

Musical parts are deployed as Textures, layered surface-defining objects containing numerous independent ParameterObjects to control pitch, tempo, rhythm, amplitude, panning, and instrument (Csound) parameters. The system includes an integrated library of Csound instruments, and supports output for external Csound instruments, MIDI, and a variety of alternative formats.