The GNU Prolog native compiler
ECLiPSe Constraint Logic Programming System
Syntax tree editor for rapid annotation of existing text
Euler Yet another proof Engine
Deductive Database with Datalog, SQL, RA, TRC, DRC
Implements the stable model semantics without grounding.
Syllog is a system for teaching logic, with anonymous answer logging
PyCLP is a Python library to interface ECLiPSe Constraint System
C#Prolog -- A Prolog interpreter written in managed C#
Java Internet Prolog (Moved to GitHub)
TuCSoN tuple-based coordination middleware
Goal-directed answer-set programming
(download) Linux Adequate"available approximately five days"
Teaching planner tool to help universities in developing countries