For constraint logic programming, ECLiPSe: http://eclipseclp.org/ http://eclipseclp.org/ It extends Prolog in various ways and was open sourced by Cisco a few y

For constraint logic programming, ECLiPSe: http://eclipseclp.org/ http://eclipseclp.org/ It extends Prolog in various ways and was open sourced by Cisco a few years back.