Developed by Diego Pettenò <email@example.com>
Hunspell is OpenOffice's spell checking library since version 2.0.3; ruby-hunspell it's a Ruby extension that binds C++ classes to Ruby classes, and allows to make use of its parsers and spell checkers without having to run a new process to pass data to.
Up to version 0.004, the extensions' sources are generated through a generator script that parses a YAML description of the C++ classes, and then compiled through CMake.
Current development version uses Rust instead, also developed by me, as this allows a more flexible code generation.
If you want to get the sources, the main development repository is tracked through GIT and can be reached through the address git://flameeyes.is-a-geek.org/ruby-hunspell.git .
You can find more information at the project page, or browse author's website.