Houdini (chess)

Houdini is a UCI chess engine developed by Belgian programmer Robert Houdart. It is influenced by open source engines IPPOLIT/RobboLito, , and Crafty. Earlier versions are free for non-commercial use (up to version 1.5a), but later versions (2.0 and onwards) are commercial. As of October 2015, Houdini 4 is the third top-rated chess engines on major chess engine rating lists after Stockfish and Komodo.

Chess commentator and video annotator CM Tryfon Gavriel compared Houdini's playing style to that of the Romantic Era of chess, where an attacking, sacrificial style was predominant.

November 25, 2013 (2013-11-25)

November 7, 2016 (2016-11-07)

November 15, 2016 (2016-11-15)

The latest stable release of Houdini comes in two versions: Houdini 5 Standard and Houdini 5 Pro. Houdini 5 Pro supports up to 128 processor cores, 128 GB of RAM (hash) and is NUMA-aware, Houdini 5 Standard only supports up to 6 processor cores, 4 GB of hash and is not NUMA-aware. As with many other UCI engines, Houdini comes with no GUI, so a chess GUI is needed for running the engine. Houdini 5 uses calibrated evaluations in which engine scores correlate directly with the win expectancy in the position.

Robert Houdart describes his engine as original and admits taking ideas from the open source programs IPPOLIT/Robbolito, and Crafty. However, some chess programmers raised suspicions that Houdart may have taken ideas from the controversial Ippolit/Robbolito source-code "too literally" as the initial base of his program.