Hydrogen

Hydrogen is an advanced drum machine created by Alessandro Cominu, an Italian programmer who goes by the pseudonym Comix. Its main goal is to bring professional yet simple and intuitive pattern-based drum programming.

Hydrogen was originally developed for Linux, but later ported to Mac OS X. An experimental build exists for Microsoft Windows but the port has since been abandoned.[1] The graphical user interface for the application uses Qt library. all code is released under the GNU General Public License. Hydrogen is free software.