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TES: The largest network of teachers in the world
Portions not contributed by visitors are Copyright 2018 Tangient LLC
TES: The largest network of teachers in the world
an UCI compatible open source chess engine developed by Tord Romstad, Marco Costalba, Joona Kiiski, and Gary Linscott [1] . Marco forked the project from version 2.1 of Tord's strong engine Glaurung, first announced by Marco in November 8, 2008 [2] , and in early 2009 Joona's Smaug, a further Glaurung 2.2 derivative, was incorporated [3] . Starting out among the top twenty engines, Stockfish has quickly climbed in strength. The name "Stockfish" reflects the ancestry of the engine. Tord is Norwegian and Marco Italian, and there is a long history of stockfish trade from Norway to Italy (to Marco's home town of Vicenza, in fact). Stockfish also references another famous "little fish", Rybka.
Table of Contents
Science versus Commerce?
There is a wide range of opinions about strong open source chess engines affecting commercial and competitive interests, as well as monetary interests from computer chess users, who obtain a top engine for free. The scientific and social value of strong open source programs is indisputable. The teamwork effort to share ideas and knowledge to write one of the strongest programs, which everybody may follow and share to learn and play for free, is definitely a challenging and motivating task, gathering both admiration and enviousness. Obviously, professional programmers of commercial chess programs are not that enthusiastic about the development, and need to improve further and/or focus more on secondary features or other business concepts like on-line play and/or user interface issues rather than on pure playing strength.Also many hobbyist chess programmers feel in antagonism as well, not only caused by Stockfish with its highly respected authors, and before by Fruit and slightly Crafty, but from Ippolit and all its successors by pseudonymous authors and disputed origin. The implications on commercial and competitive computer chess are not quite clear, but presumably the decrease in number of participants of over the board tournaments will progress and clone suspicions may float like a Sword of Damocles over the scene, whether programmers took ideas too literally or not.
Fishtest
The Stockfish Testing Framework called Fishtest [5] is a web application written by Gary Linscott [6] [7] mainly in Python under the Pyramid Application Development Framework [8] , to distribute games across different machines to reduce the test latency and increment throughput. Started in early 2013 with Stockfish 3.0, Fishtest has hundreds of contributors, as of May 2014, 744 testers and 52 developers [9] active in testing ideas and tweaks [10] , to make Stockfish the strongest open source or even chess program of the world [11] .Evaluation Guide
Since April 2017 the interactive Stockfish Evaluation Guide is available to explore Stockfish's evaluation with a JavaScript implementation running in a browser [12] . One may enter a FEN string of a position, to get the resulting score of the main evaluation term considering the game phases within its tapered evaluation, and may navigate through the tree of subterms and features with its particular characteristics for the given position [13] .Tournament Play
Stockfish is top contender of the prestigious Thoresen Chess Engines Competition (TCEC), reaching the superfinals since season 4, losing season 4 from Houdini and season 5 from Komodo TCEC, both narrow matches with 23 - 25, but won the season 6 superfinal versus Komodo 7 conveniently with +13=45-6 and 35½ - 28½. Successor Stockfish 141214 qualified for the TCEC Season 7 Superfinal in December 2014, versus Komodo again, this time with the better end for Komodo 8 successor 1333 with 33½ - 30½. About one year later at TCEC Season 8, again Komodo and Stockfish qualified for the TCEC Season 8 Superfinal, finished with 53½ - 46½ in favour to Komodo 9.3x [14] , but in the following year Stockfish 8 won the superfinal conveniently this time versus the new Houdini 5 with 54½ - 45½..
GM+Rybka vs. Stockfish
On July 19, 2014, Stockfish 5 played a four game match versus Daniel Naroditsky plus Rybka 3 (2008), 45 minutes plus 30-second increment. Stockfish won 3½ - ½ [15] [16] . A few weeks later the experiment continued with Hikaru Nakamura in Burlingame, California [17] . Supported two games by Rybka 3, Nakamura lost ½ - 1½, two games with pawn odds (Stockfish both Black without h- and b-pawn) ended ½ - 1½ in favour to Stockfish 5 as well. It played the latest development build compiled for OS X running on a 3 GHz 8-Core Mac Pro [18] .Selected Features
[19]Board Representation
BMI2 - PEXT Bitboards (not recommend for AMD Ryzen [20])
Search
Evaluation
[22] [23]Misc
SPSA
Release Dates
Ports
Derivatives
See also
Publications
Videos
Forum Posts
2008
2009
2010
2011
2012
2013
2014
2015
Explanation for non-expert? by Louis Zulli, CCC, February 16, 2015 » Parallel Search
2016
Re: Stockfish 7 and partial 6 piece syzygy problem? by Marco Costalba, CCC, September 01, 2016
2017
2018
External Links
Chess engine
Stockfish Testing Framework » Fishtest
Stockfish Evaluation Guide » Stockfish Evaluation Guide
FishCooking - Google Groups a discussion group for developers and testers of Stockfish chess engine
SPSA Tuner for Stockfish Chess Engine » SPSA
Rating Lists
Matches
Interviews
Misc
References
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