Purrr is a Forth dialect for microcontrollers.

The main goal of Purrr is to fill the gap between low and high level languages for 8-bit Flash ROM based microcontrollers. It has the efficiency of assembler, being in effect nothing more than a collection of assembly macros, while the use of a stack makes operations local, easing composition of low level building blocks into higher level constructs. Purrr is a cross compiled Forth dialect, which nevertheless tries to preserve the interactive nature of Forth, one of the greater merits of the Forth programming paradigm. You can add and test code while your application is running. In short, Purrr is a tool for live incremental bottom up programming.

Currently Purrr is implemented for the Microchip PIC18 microcontroller architecture. It is used to write the system software for the [wiki:CATkit CATkit] board. For more information, see the [http://zwizwa.be/darcs/brood/tex/purrr.pdf Purrr Manual], and the introduction to the [http://zwizwa.be/darcs/brood/tex/synth.pdf Sheep] synth.