epicycle is a GUI sequencer based on libsequoia.
epicycle was developed as a personal testing and demonstration platform for libsequoia. it was never intended to be released. as such, it's a bit rough around the edges, with an obscure interface and zero documentation. but enough people have asked for example code using libsequoia, that i've decided to swallow my pride and publish it anyway. so just be aware: this is a half-baked project.
sudo apt-get install qt5-default g++
You'll also need libsequoia, which is hosted here
qmake
make
sudo make install
./bin/epicycle
N creates a new sequence
P creates a new outport
Q creates a new inport
HJKL navigate around the steps
T inserts (or removes) a trigger
Ctrl-JK adjusts the note value
Shift-N to set the sequence Name
Shift-T to set the sequence Transpose
Shift-D to set the sequence clock Divide
Shift-M to Mute/unMute the sequence
Spacebar to start/stop the sequence
Right-click within the sequence to select the outport
Right-click on the outport to set its name
Right-click on the inport to set its various parameters
First/Last step can be set by left/right-clicking under the steps