Huh. I worked at FORTH, Inc. a little in the 80s and would've said it's fine for systems programming: use the assembler vocabulary. I can see running into limit

Huh. I worked at FORTH, Inc. a little in the 80s and would've said it's fine for systems programming: use the assembler vocabulary. I can see running into limits without that, but with it it's better than a macro assembler. But I've never tried Open Firmware beyond hello-world.