Open Source Prolog Interpreters

GNU Prolog is a free implementation (under GPL) of the logic programming language PROLOG. It can compile to native machine code which is extremely fast in execution. Another feature is the included constraint solver.

The Yap Prolog System is a ISO-compatible high-performance Prolog compiler. Yap is widely considered one of the fastest available Prolog systems. Yap supports coroutining, CLP(QR), CHR, and depth-bound search. Tabling and parallelism are in development.

XGP is an integrated development environment that extends GNU Prolog to work with Cocoa under Macintosh OS X. It provides user interface and graphics facilities largely compatible with MacProlog32 by LPA. Requires Mac OS X version 10.2.1 or greater.

Prolog compiler and interpreter for the .Net 2.0 framework.

The CommGen platform is intended to be a simple, scalable integration platform for small to medium problem sets. The architecture is simple, consisting of a distributed kernel, distributed O/S, agent and application layer.

FOML is an expressive logic rule language that supports object modeling, analysis, and inference. It naturally supports model-level activities, such as constraints (extending UML diagrams), dynamic compositional modeling, analysis and reasoning about models, model testing, design pattern modeling, specification of Domain Specific Modeling Languages, and meta-modeling. FOML can reason about: 1. The model meta-data (meta-model level reasoning, or syntax reasoning) 2. Data level: reason about a model and its data (instance model, i.e., diagram) FOML is built as a semantic layer on top of PathLP - a compact logic rule language of guarded path expressions, an adaptation of a subset of F-logic.

Galliwasp is an answer set programming (ASP) system utilizing a unique top-down, goal-directed execution method.

JPIE is an implementation of an Open Source Java to Prolog/Prolog to Java interoperability mecanism based on the Java VM.