I got that bass from someone in the GBJAM Discord last year! Let me know if you want me to send it to you. It's just a hex string that you can plug into a tracker, works in Game Boy ROMs too.
Thank you for the kind words. I'm planning to do a little bit more with this post-jam. Some progression and/or a win condition would help satisfy while keeping the game bite-sized. I took some notes from GOLD RUSH 1898.