There a few good homebrew tools and libraries available. We did a gameboy game for a Ludum dare a short while back, and while it's certainly not pretty z80, the

There a few good homebrew tools and libraries available. We did a gameboy game for a Ludum dare a short while back, and while it's certainly not pretty z80, the tooling got the job done. (Be gentle, it was my first time trying to do anything serious directly in assembly and we had a 72-hour time limit.) https://github.com/zeta0134/ludum-dare-42 https://github.com/zeta0134/ludum-dare-42 We used the RGBDS assembler and its built in tools to make the thing, mostly because that runs on Linux and that's what we both wanted to develop on. My partner did the graphics and I got a decent flow going from LibreSprite using RGBGFX for the conversions. https://github.com/rednex/rgbds https://github.com/rednex/rgbds I'll admit that I did have a major advantage going in, having written a mostly functional gameboy emulator already, but emulating a system is very, very different from programming against its constraints. There are decent software libraries floating around, but since there's no real standard way to leverage the hardware once you get past the basics (even commercial games had wildly varying strategies from company to company) the best tool in the belt is probably your documentation. Pan docs and the various wikis were instrumental in understanding how to leverage the hardware to do what we wanted.