Clips a Tool for Building Expert Systems (clipsrules.net)

CLIPS (C Language Integrated Production System) is a rule‑based programming language originally developed at NASA’s Johnson Space Center between 1985 and 1996 for building expert systems. Designed as a production‑rule system and written in C for maximum portability, CLIPS lets developers encode domain knowledge as rules and facts so heuristic solutions can drive problem solving where explicit algorithms are impractical. It has been public domain software since 1996 and runs on a wide variety of platforms. For the AI/ML community, CLIPS remains significant as a compact, deterministic tool for rapid prototyping, knowledge engineering, and integration with legacy or resource‑constrained systems. Unlike statistical ML models, rule‑based systems make decision logic explicit and maintainable, which is valuable for explainability, verification, and domains with clear expert heuristics (e.g., diagnostics, configuration, and control). Its C implementation aids embedding in larger systems and cross‑platform deployment, making CLIPS a pragmatic alternative or complement to data‑driven approaches when transparency and rule maintenance are priorities.