GNU Chess

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GNU Chess, the open source chess engine of the Free Software Foundation. GNU Chess was initially written by Stuart Cracraft in the mid 80s, joined by John Stanback who contributed his own code to GNU Chess 2 and 3 which was laboriously and meticulously well-written. Dozens of developers have enhanced GNU Chess over the times. Version 5 was a complete rewrite by Chua Kong Sian, incorporating his chess program Cobalt and Cracraft's Gazebo. Fabien Letouzey is the primary author of GNU Chess 6, based on Fruit 2.1. =Fidelity Match= In 1990, GNU Chess 1.55 with Hans Eric Sandström's fast move generator defeats Fidelity in a 10 game match : A 10 game match was conducted between GNU Chess 1.55 running on a Sun SPARCstation-1 and the strong commercial chess machine Fidelity Mach 3. Fidelity Mach 3 is officially rated USCF 2265 (2200 is master). Most observers acknowledge it is a true master. The match result was 7-3 in GNU's favor. After various corrections, we arrive at a putative rating of around 2330 (strong master) for GNU Chess 1.55 on this machine. This result was most unexpected since prior versions of GNU Chess had scored no more than 3 points out of 10 against the Mach 3. The big leap appears to come from: (1) the inclusion of Hans Eric Sandstrom's fast move generator and (2) the Sparcstation-1, which is (apparently) particularly suited to speedy chess processing. Minor modifications to the book, draw factor, and thinking on opponent's time have also helped. Please remember this rating is based on a short match result. Certain moves GNU Chess plays are clearly non-master in quality. Computer masters generally achieve their strength through accuracy of tactics, not subtle positional moves.

=Authors=

Primary

 * Stuart Cracraft, Versions 1, 2, 5
 * John Stanback, Versions 2, 3, 4
 * Chua Kong Sian, Version 5
 * Fabien Letouzey, Version 6

Contributors

 * Jim Aspnes » ACM 1987
 * Antonio Ceballos
 * Lukas Geyer
 * Hans Eric Sandström
 * Jay Scott » ACM 1987
 * Michel Van den Bergh
 * Simon Waters

=See also=
 * Chess Engine Communication Protocol
 * Cobalt
 * Free Software Foundation
 * Gazebo
 * GNOME Chess
 * NeuroChess
 * SCP
 * Table-driven Move Generation
 * WinBoard
 * XBoard

=Publications=
 * T.M. Balajee, Adithya Udupa, Anil Kumar, D. Namratha (2009). Aggrandizement of Board Games’ Performance on Multi-core Systems: Taking GNU-Chess as a prototype. BMS College of Engineering, Faculty mentor: Professor Ashok Kumar, Intel® Developer Zone » Parallel Search
 * Tomohiko Mitsuta, Lothar M. Schmitt (2010). Optimizing the Performance of GNU-chess with a Genetic Algorithm. HC 2010, pdf » Genetic Algorithms

=Forum Posts=

1989

 * Changes to gnuchess1.52 by Tom Vijlbrief, gnu.chess, December 8, 1989

1990 ...

 * GNU Chess 1.55 ready by Stuart Cracraft, gnu.chess, January 2, 1990
 * GNU Chess 1.55 vs. Fidelity Mach 3 by Stuart Cracraft, gnu.chess, January 3, 1990
 * gnuchess.book in Lisp by Steven Edwards, gnu.chess, January 23, 1990
 * Re: IBM PC front end for GNU chess by Stuart Cracraft, gnu.chess, December 17, 1990
 * Help needed -- can't compile xchess by Heinz Herbeck, gnu.chess, March 17, 1992
 * Post information from Gnuchess 4.0 by Chua Kong Sian, gnu.chess, June 12, 1992
 * GNU Chess wins London computer chess tourney by Stuart Cracraft, gnu.chess, August 17, 1992 » UPCCC 1992
 * Gnuchess 4.0 for DOS by Chua Kong Sian, gnu.chess, January 29, 1993
 * Re: Gnu Chess for the Mac by Urban Koistinen, gnu.chess, April 16, 1993 » Macintosh
 * QMW computer chess by Don Beal, rec.games.chess, August 19, 1993 » UPCCC 1993
 * gnu.chess FAQ by Tim Mann, rgcc, January 4, 1994
 * Fix for ScoreKBNK routine by Chua Kong Sian, gnu.chess, February 11, 1994
 * KILLT & HISTORY by Chua Kong Sian, gnu.chess, February 19, 1994
 * Search extensions on recaptures by Chua Kong Sian, gnu.chess, March 22, 1994
 * Bug fixes for PawnValue by Chua Kong Sian, gnu.chess, March 24, 1994
 * Speed up Gnuchess by Vincent Diepeveen, gnu.chess, April 18, 1994
 * Speed up UpdatePieceList by Vincent Diepeveen, gnu.chess, April 18, 1994
 * Alpha-beta inconsistencies by Chua Kong Sian, gnu.chess, May 20, 1994
 * Bug in ttable.c wrt storing of mate scores by Chua Kong Sian, gnu.chess, May 20, 1994
 * Patches for eval.c by Chua Kong Sian, gnu.chess, May 28, 1994
 * Pawn ram code in gnuchess by Chua Kong Sian, gnu.chess, June 18, 1994

1995 ...

 * Killer moves by Chua Kong Sian, gnu.chess, March 21, 1995
 * Re: request ... by Stuart Cracraft, gnu.chess, June 16, 1995
 * Re: The KISS Chess Program Project - Overview - ABSEARCH.TXT (0/1) by Tom Kerrigan, rgcc, August 12, 1997
 * GNU move generation by Jan Willem de Kort, rgcc, March 18, 1998 » Move Generation
 * Sever Clutter with Clones of GnuChess/Crafty by Stuart Cracraft, CCC, January 27, 1999
 * GNU Chess 5 by Stuart Cracraft, gnu.chess, October 10, 1999

2000 ...

 * GNUChess 5.0.. or later... if there is later... by Peter Skinner, CCC, January 03, 2001
 * The marvelous showing of GnuChess at CCT3 by Dann Corbit, CCC, May 28, 2001 » CCT3
 * Wb2UCI and Problems with ExChess4.03a and GnuChess4.0.8 by Arturo Ochoa, Winboard Forum, July 24, 2003 » Wb2UCI, InBetween
 * First draw against GnuChess by Sven Reichard, CCC, November 26, 2003
 * Who started GNUChess? by Jamie Stegner, CCC, March 26, 2004
 * Controversy about who's 1st author of Gnuchess..........John? or Stuart? by Jamie Stegner, CCC, March 29, 2004

2005 ...

 * Re: gnuchess/xboard protocol by Hans Eric Sandström, gnu.org, May 19, 2006
 * GNU 5.07 by Fernando Villegas, CCC, July 17, 2007
 * Did someone mention the GNUChess move Generator? by Michael Sherwin, CCC, November 12, 2007 » Move Generation
 * PSP GNU CHESS: Chess game for PSP v1.0.3 by zx-81 in Chess-Game, November 17, 2007

2010 ...
2011 2012 2013 2014
 * GNUChess for Android by Michel Van den Bergh, CCC, December 24, 2010
 * GNU Chess v6 pretest by Antonio Ceballos, info-gnu Archives, January 23, 2011
 * GNU Chess 6 (= Fruit) by Harm Geert Muller, CCC, January 25, 2011 » Fruit
 * GNU Chess 5.08 released by Simon Waters, info-gnu Archives, January 30, 2011
 * GNU Chess 6 released by Antonio Ceballos, info-gnu Archives, April 27, 2011
 * GNU Chess release 6.0.1 by Antonio Ceballos, info-gnu Archives, September 08, 2011
 * gnuchess 5.07.173b by Michel Van den Bergh, CCC, September 19, 2011
 * GNU Chess release 6.0.2 by Antonio Ceballos, info-gnu Archives, March 04, 2012
 * GnuChess 5.07.174.1b by Michel Van den Bergh, CCC, October 20, 2012
 * GNU Chess release 6.0.3 by Antonio Ceballos, info-gnu Archives, March 11, 2013
 * GNU Chess 5.50 by Michel Van den Bergh, CCC, April 16, 2013
 * GNU Chess release 6.1.0 by Antonio Ceballos, info-gnu Archives, November 10, 2013
 * GNU Chess 6.1.1 by Antonio Ceballos, info-gnu Archives, November 23, 2013
 * GNU Chess 6.1.2 by Antonio Ceballos, info-gnu Archives, July 30, 2014
 * GNU Chess 5.60 by Michel Van den Bergh, CCC, November 22, 2014

2015 ...
2016 2017
 * GNU Chess release 6.2.1 by Antonio Ceballos, info-gnu Archives, January 04, 2015
 * Building GNU Chess 5.07 by Harm Geert Muller, CCC, October 01, 2015
 * GNU Chess 6.2.2 by Antonio Ceballos, info-gnu Archives, October 17, 2015
 * Short questions (1): GNUChess 5.6 or 6.22 ... differents? by Frank Quisinsky, CCC, October 23, 2015
 * SourceForge . GNUChess 6.2.2 for Windows by Norbert Raimund Leisner, CCC, January 21, 2016
 * GNU Chess 6.2.3 by Antonio Ceballos, gnu.chess, September 20, 2016
 * GNU Chess 6.2.3 Release by Michael B, CCC, October 06, 2016
 * GNU Chess 6.2.4 by Antonio Ceballos, info-gnu Archives, October 29, 2016
 * GNU Chess 6.2.5 by Antonio Ceballos, info-gnu Archives, July 25, 2017
 * GNU Chess 6.2.5 release by Norbert Raimund Leisner, CCC, August 08, 2017
 * Is gnu chess what I am looking for ? by David Wilson, gnu.chess, November 05, 2019

2020 ...

 * GNU Chess 6.2.6 released by Antonio Ceballos, gnu.chess, April 18, 2020
 * GNU Chess 6.2.7 released by Antonio Ceballos, gnu.chess, May 31, 2020

=External Links=

Chess Engine

 * GNU Chess - Free Software Foundation
 * GNU Chess on Tim Mann's Chess Pages
 * GNU Chess from Wikipedia
 * GNU Chess, MobyGames
 * Classic Computer Chess - ... The programs of yesteryear by Carey, hosted by the Internet Archive
 * rec.games.chess.computer GNU Chess and XBoard: Frequently Asked Questions
 * GitHub - heisencoder/gnuchess: Git fork of GNU Chess 5
 * Index of /Toga/gnuchess-release by Michel Van den Bergh
 * Index of /GnuCheese by Michel Van den Bergh

Rating

 * GNU Chess 5.50 64-bit in CCRL 40/40
 * GNU Chess 5.50 64-bit in CCRL 40/4 FRC

News Group

 * gnu.chess (early years have less spam)

=References=

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