This past month, romhacker and developer kandowontu, also known for his Starfox EX romhack for the original Starfox and several FastROM hacks for over 60 titles for the SNES, alongside a team of artists and other coders, have been working lately on a new homebrew game for the Nintendo Entertainment System (NES) titled "Famidash", a demake of the popular rhythm-action platformer indie game Geometry Dash developed originally by Robert Topala on 2013 (also be found on Steam).
Famidash is currently being developed in what seems to be a combination of C language alongside 6502 assembly, which makes for an interesting combination given how most retro games were entirely developed in assembly language, only starting using C around the time the PlayStation and Nintendo 64 came along.
For those interested in trying it out, Famidash is currently in a beta/demo stage, but developer kandowontu is pushing fixes frequently on the Famidash GitHub repository with the latest update being v4.05.1 released just a week ago.
Famidash source code at GitHub
Famidash Discord server