If you just want to try CHR without much hassle, try the WebCHR Interactive Demo.
The Leuven CHR System is a state-of-the-art CHR system. It is available in the following Prolog systems:
Other CHR(Prolog) systems:
- CHRrp: CHR extended with rule priorities
- CHRat: CHR with ask and tell, a modular CHR system
- CHORD: an object-oriented extension of CHRv
- ToyCHR: a pure Prolog implementation
- HAL includes a CHR system
- ECLiPSe includes a CHR system
- CHR in Curry (a functional logic language)
There are several CHR systems for Haskell:
- STM-based concurrent CHR implementation
- CCHR: another STM-based concurrent CHR implementation
CCHR is an efficient implementation of CHR in C.