The Ruby Language Toolkit provides classes for creating context-free grammars, lexers, parsers, and abstract syntax trees.

Aubio is a tool designed for the extraction of annotations from audio signals. Its features include segmenting a sound file before each of its attacks, performing pitch detection, tapping the beat and producing midi streams from live audio.

Gem to interface with secret rabbit code

The Ruby Code Generation Toolkit provides classes for generating LLVM IR and native object code.

FFI bindings to libgroove