MIDI Sequencing for Haiku

Sequitur is a BeOS/Haiku-native MIDI sequencer with a MIDI processing add-on architecture. It allows you to record, compose, store, and play back music from your computer. Sequitur is designed for people who like to tinker with their music. It facilitates rapid, dynamic, and radical processing of your performance.


  • An add-on architecture for processing MIDI and performing MIDI effects. Change a track's velocity, apply echo, add chorus, change it's key signature, etc.
  • MIDI processing is integrated with editing: Paint with echo effects, paint chords in key, etc.
  • Easily rearrange songs with familiar phrase operations.
  • Customize your interface with skinning.
  • Achieve special effects with tool properties: Turn on gradual delete and slowly rub out MIDI events.
  • Full support of Haiku's advanced MIDI services: All Midi2-compatible software is automatically available.
  • Record, edit, and playback note, program change, control change, and pitch bend MIDI data.
  • Read and write standard MIDI files.

This version (2.1.2) of the source compiles and runs under Haiku, without any so-far-detected limitations. It is essentially identical in behaviour to the last 2.1 BeOS version, except that the FilePanels are a bit smarter (they filter to show only MIDI files, and preserve the working directory). It now saves files with MimeType 'audio/midi', but recognizes 'audio/x-midi' and 'audio/mid' as well.

The "devkit" folder in the BeOS original has been omitted from the user package because it has not yet been checked that it matches the current source [it almost certainly doesn't]. As the complete source is now freely available it is probably redundant anyway.


These have been superseded by version 2.1.3 on HaikuDepot, but are left here for now…
Sequitur 2.1.2 (3.73MB zip)
Complete MIDI Sequencing for Haiku. Download and unpack anywhere convenient for use.
Sequitur 2.1.2 hpkg (4.32MB hpkg)
Working recompiled version for current Haiku in Haiku-Package form. Download and drag to /boot/system/packages or ~/config/packages.
Original Sequitur 2.1.2 hpkg (3.61MB hpkg)
This is the original hpkg which no longer runs in recent updates of the OS. If you have an older installation it might work where the newer version won't.
Source for building the above version (2.89MB zip)
This source is complete for building Sequitur 2.1.2, but has been trimmed of about 5MB of code that is unused here. The complete original source from ARP, now patched to match the latest version, is available at HaikuArchives.
It seems that the TimGM Sounfont available from HaikuDepot is still not the fixed one!! Three of the instruments (admittedly not all that popular ones) are unusable in certain key ranges: "Harmonica" (23), "Bandoneon" (or "Tango Accordion" 24), and "Whistle" (79). I fixed the font several years ago, and passed it back to the author, but it doesn't seem to get propagated... If you want to experience the worst two instruments (Bandoneon and Whistle, here's a brief demo file! The really fixed version is here as a Zip file (5.31MB) or an hpkg (5.31MB)

There are may other soundfonts to be found on the web. One I find I use most is "General User" (29.83MB — get FluidSynth-version 1.44).

This software and all accompanying documentation is released as freeware. Users are granted the right to use this software without restriction, and distribute it freely. This software comes with no guarantees or warranties. The authors are not responsible in any way for any damage that occurs as a result of using this software.

Sequitur is Public Domain. It was originally Copyright ©2000-2002 by Angry Red Planet, Eric Hackborn, Dianne Hackborn, and Daniel Civello. The authors have generously transferred the code to Public Domain, and donated the original source to the HaikuArchives on GitHub.

created by
Angry Red Planet

               Pete Goodeve
               Berkeley, California

         e-mail: pete@GoodeveCa.NET