Qtractor is an Audio/MIDI multi-track sequencer application written in C++ with the Qt framework. Target platform is Linux, where the Jack Audio Connection Kit (JACK) for audio, and the Advanced Linux Sound Architecture (ALSA) for MIDI, are the main infrastructures to evolve as a fairly-featured Linux desktop audio workstation GUI, specially dedicated to the personal home-studio.

qtractor.sourceforge.io
en.wikipedia.org/wiki/Qtractor