kkreiger was by Farbrausch who make some of the most incredible demos out there eg Quantum Mysterium from last year - https://www.youtube.com/watch?v=DAyQeX8a-Bw - that's done in 48Kb of code.
That's so awesome! Especially because it's inspired by Candide Thovex's One of those days. Link for those who aren't familiar(he also used CGI for some of the things that would be super dangerous, he skied the line, but people weren't actually there): https://www.youtube.com/watch?v=ygxufRprWpY
This one is a hybrid with some predefined (tiny!) assets and some procedural generation (instruments, texture placement).