The OTTO is a complete hardware and software solution, with synths, a sampler, effects, sequencers, and studio modules heavily inspired by the OP-1, but it is not an OP-1 clone. OTTO is not, and will never be, a commercially aimed product. It is open source by nature, in both hardware and software. If you want an OTTO, you're going to get your hands dirty, if not with the code, at least with the hardware.

https://github.com/topisani/OTTO