Señor Staff is an open-source music composition app for Mac OS X. It features a staff-based interface (rather than a tracker interface) for natural entry and readability, and supports playback to any MIDI device. Emphasis is placed on user efficiency and automated enforcement of musical constraints.

Version 0.8.2 of Señor Staff is now available for download.

Development on Señor Staff is currently inactive. There were some changes to OS X’s MIDI subsystem in 10.5 which cause several known bugs in Señor Staff, so use at your own risk.

Feel free to download the source and use however you like.

Bug reports and feature requests are always welcome.