Sjeng is a

chess engine In computer chess, a chess engine is a computer program that analyzes chess or chess variant positions, and generates a move or list of moves that it regards as strongest. A chess engine is usually a back end with a command-line interface wit ...

written by

Gian-Carlo Pascutto Gian-Carlo Pascutto (born 1982) is a Belgian computer programmer. He is the author of chess engine Sjeng and Go software Leela, and the original author of the free and open-source Go software Leela Zero. Gian-Carlo also authored many core compone ...

based on Faile, written by Adrien Regimbald. There are two major versions of Sjeng: the original

open source Open source is source code that is made freely available for possible modification and redistribution. Products include permission to use the source code, design documents, or content of the product. The open-source model is a decentralized sof ...

version called Sjeng (also now known as Sjeng old or Sjeng free) and Deep Sjeng, a closed source commercial version.

Sjeng ‘Free’

According to the Sjeng website “Sjeng was written by Gian-Carlo Pascutto with help from Adrien Regimbald, Daniel Clausen, Dann Corbit, Lenny Taelman, Ben Nye, Ronald De Man, David Dawson, Tim Foden and Georg von Zimmermann.” The AUTHORS file in the Sjeng distribution states that “Sjeng is written by Gian-Carlo Pascutto, based on work done by Adrien Regimbald.” Unlike most other chess engines Sjeng supports several popular

chess variants A chess variant is a game related to, derived from, or inspired by chess. Such variants can differ from chess in many different ways. "International" or "Western" chess itself is one of a family of games which have related origins and could be co ...

Crazyhouse Crazyhouse (also known as drop chess, mad chess, reinforcement chess, turnabout chess and schizo-chess) is a chess variant in which captured enemy pieces can be reintroduced, or ''dropped'', into the game as one's own. The drop rule resembles tha ...

, Suicide, Losers and, when playing on a chess server, Bughouse. Starting with Mac OSX 10.4 Sjeng has been distributed as the engine behind the graphical “

Chess Chess is a board game for two players, called White and Black, each controlling an army of chess pieces in their color, with the objective to checkmate the opponent's king. It is sometimes called international chess or Western chess to disti ...

” Mac application. The first version with source code under the

GPL The GNU General Public License (GNU GPL or simply GPL) is a series of widely used free software licenses that guarantee end users the four freedoms to run, study, share, and modify the software. The license was the first copyleft for general us ...

was Sjeng 7 released to

SourceForge SourceForge is a web service that offers software consumers a centralized online location to control and manage open-source software projects and research business software. It provides source code repository hosting, bug tracking, mirrorin ...

on 4/15/2000. The last open source version was Sjeng 11.2, released on 1/2/2002. With version 12 Sjeng went back to being closed source, although still free. Version 12 contained many changes, including a switch to

bitboard A bitboard is a specialized bit array data structure commonly used in computer systems that play board games, where each bit corresponds to a game board space or piece. This allows parallel bitwise operations to set or query the game state, or de ...

architecture and the removal of variant support. Version 12.7 was released concurrently with version 11.2 on 1/2/2002. Several more versions were released culminating with version 12.13 on 5/3/2002.

Deep Sjeng

The next iteration of the chess engine was named Deep Sjeng 1.0 and released as a commercial program on 3/3/2003. It featured

multiprocessor Multiprocessing is the use of two or more central processing units (CPUs) within a single computer system. The term also refers to the ability of a system to support more than one processor or the ability to allocate tasks between them. There ar ...

support and was estimated to be 200 rating points stronger than Sjeng Free. The last version of Deep Sjeng won the World Computer Speed Chess Championship in 2008. Deep Sjeng is no longer for sale.

Tournaments

Deep Sjeng participated in six

World Computer Chess Championships World Computer Chess Championship (WCCC) is an event held periodically since 1974 where computer chess engines compete against each other. The event is organized by the International Computer Games Association. It is often held in conjunction with ...

, then retired after tying for first place in the 17th Championship. Deep Sjeng actually tied for second place, however the winner,

Rybka Rybka is a computer chess engine designed by International Master Vasik Rajlich. Around 2011, Rybka was one of the top-rated engines on chess engine rating lists and won many computer chess tournaments. After Rybka won four consecutive World ...

, was disqualified for plagiarism. Sjeng won the

World Computer Speed Chess Championship World Computer Speed Chess Championship is an annual event organized by the International Computer Games Association where computer chess engines compete against each other at blitz chess time controls. It is held in conjunction with the World Co ...

in 2008, and the

World Computer Chess Championship World Computer Chess Championship (WCCC) is an event held periodically since 1974 where computer chess engines compete against each other. The event is organized by the International Computer Games Association. It is often held in conjunction with ...

in 2009. It also won the

Internet Computer Chess Tournament The Internet Chess Club (ICC) is a commercial Internet chess server devoted to the play and discussion of chess and chess variants. ICC had over 30,000 subscribing members in 2005.John Black, Martin Cochran, Martin Ryan Gardner"Lessons Learne ...

in 2010 and 2011.

References

External links

* * ;Wiki * * {{cite web , url= https://chessprogramming.wikispaces.com/Deep+Sjeng , title= Deep Sjeng , website= Chess Programming , series= Wiki , url-status= dead , archive-date= July 12, 2018 , archive-url= https://web.archive.org/web/20180712203303/https://chessprogramming.wikispaces.com/Deep+Sjeng Chess engines