Crustacean Chirpy Chip Challenge

There was a brief discussion on what makes a microcontroller/language/etc stack considered ready for prime-time, what a "real" program is in this context.
While many hackers will say that your toaster should run doom (or at least linux), I felt this undersold what makes microcontrollers special - real time peripherals and IO.

Consequently, we present CCCC: the Crustacean Chirpy Chip Challenge.
Using the microcontroller, language, etc of your choice, you must implement a MIDI synth. The specifications for the challenge:

The rest is up to you.
Use the most outlandish stack you desire. Play it safe with C and the SDCC. MIDI over USB or serial? Your call. Polyphony? If you want, for kudos. We don't have a high bar.

Participation is opt in, hopefully to keep you motivated. We'll list the "competitors" (as much as this could be competitive in any way) below. Say hello on ##crustaceans or #lobsters if you want to join in.
If you have a progress page, we can link that too.
Change your mind, or embarrassed by your (non-)progress? That's cool, we'll opt you out, too.