After more than a year of development, sucofunk released Beatmaker's Sketchbook, a Teensy 4.1 based sampler and sequencer. Designed as an Open Source alternative to the OP1 and MPCs, it follows a "Sample, Sketch, Arrange, Play" workflow to help take your ideas from simple noodling to live performances.

https://www.pjrc.com/beatmakers-sketchbook-sampler-sequencer/