ARexx was developed on an Amiga 1000 computer with 512K bytes of memory and two floppy disk drives. The language prototype was developed in C using Lattice C, and the production version was written in assembly-language using the Metacomco Assembler. The documentation was created using the TxEd editor, and was set in TEX using Amiga TEX. This is a 100% Amiga product.