for imperative programming languages that are used to encode and solve a constraint satisfaction problem. Cassowary constraint solver, an open source project for constraint satisfaction (accessible from C, Java, Python and other languages). Comet, a commercial programming language and toolkit Gecode, an open source portable toolkit written in C++ developed as a production-quality and highly efficient implementation of a complete theoretical background. Gelisp, an open source portable wrapper of Gecode to Lisp. http://gelisp.sourceforge.net/ IBM ILOG CP Optimizer: C++, Python, Java, .NET libraries (proprietary, free for academic use). Successor of ILOG Solver/Scheduler, which was considered the market leader in commercial constraint programming software as of 2006 JaCoP, an open source Java constraint solver. OptaPlanner, another open source Java constraint solver. Koalog, a commercial Java-based constraint solver. logilab-constraint, an open source constraint solver written in pure Python with constraint propagation algorithms. Minion, an open-source constraint solver written in C++, with a small language for the purpose of specifying models/problems. ZDC, an open source program developed in the Computer-Aided Constraint Satisfaction Project for modelling and solving constraint satisfaction problems. Other constraint programming languages Constraint toolkits are a way for embedding constraints into an imperative programming language. However, they are only used as external libraries for encoding and solving problems. An approach in which constraints are integrated into an imperative programming language is taken in the Kaleidoscope programming language. Constraints have also been embedded into functional programming languages. See also Constraint satisfaction problem Constraint (mathematics) Candidate solution Boolean satisfiability problem Decision theory Satisfiability modulo theories Knowledge-based configuration References External links CSP Tutorial Videos Constraint Satisfaction Lecture by Dr Madhu Sharma (3:47) Introduction of Constraint Satisfaction Problems by Edward Tsang (7:34) Constraint Satisfaction Problems by Wheeler Ruml (9:18) Lecture on Constraint Satisfaction Problems by Indian Institute of Technology Madras (51:59) Lecture on CSPs (1:16:39) Lecture on Constraint Satisfaction Problems by Berkeley AI (1:17:38) Graduate Course in AI 5: Constraint Satisfaction by Prof Mausam (1:34:29)