CrustyBASIC – a BASIC cross-compiler for retro machines by telengard

CrustyBASIC is a BASIC cross-compiler for writing programs that run on vintage computers and newer desktop systems. The compiler runs on Windows, macOS, and Linux, and translates BASIC source into native machine code. Its targets span Apple II models, Atari computers and consoles, Commodore systems including the C64 and Amiga, TRS-80 Color Computer, Nintendo NES, Sinclair ZX81 and Spectrum, and 16-bit MS-DOS. It can also produce Windows programs with graphics and Linux programs with text output. The project is in development, with new targets and community-requested updates appearing in recent releases.

A central aim is to let programmers reuse familiar BASIC, including older listings and tokenized programs, rather than learn a separate syntax for each machine. Compile-time options control tradeoffs such as speed and program size, as well as cartridge output, math libraries, and memory layouts. Directives support syntax rewriting and inclusion of code or resources, while portable APIs for graphics, sprites, tiles, sound, input, and files help adapt programs across systems. A short program can be built into a runnable file with one command, or compiled to assembly for further use. The download includes a usage guide, language reference, and examples, and is offered as a name-your-own-price tool with builds for major desktop platforms.