asm21 - a small (4k) native assembler for Z80-based machines - is less than 4k in size - uses a bytecode source format to save space - runs on the Z80 CPU itself - emits code for the Z80 CPU - should be easily ported to any Z80-based machine So why would you need this? This is part of the Micro21 project, a microcomputer that comes with all the tools required to make such a computer itself, without the help of another machine. Due to the small size (only 4k, hopefully) this little assembler could be useful on other machines as well. For example you might want to try it on a Sinclair ZX Spectrum or port it to CP/M. You need https://github.com/maly/asm80-node to build this.