Komodo (chess)

Komodo is a UCI chess engine developed by Don Dailey and Mark Lefler, and supported by chess author and evaluation expert GM Larry Kaufman. Komodo is a commercial chess engine but older versions (12 and older) are free for non-commercial use. It is consistently ranked near the top of most major chess engine rating lists, along with Stockfish and Leela Chess Zero.^{[1][2][3][4][5]}

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History[]

Komodo was derived from Don Dailey's former engine Doch in January 2010.^[6] The first multiprocessor version of Komodo was released in June 2013 as Komodo 5.1 MP.^[7] This version was a major rewrite and a port of Komodo to C++11. A single-processor version of Komodo (which won the CCT15 tournament in February earlier that year) was released as a stand-alone product shortly before the 5.1 MP release. This version, named Komodo CCT, was still based on the older C code, and was approximately 30 Elo stronger than the 5.1 MP version, as the latter was still undergoing massive code-cleanup work.^[8]

With the release of Komodo 6 on 4 October 2013, Don Dailey announced that he was suffering from an acute form of leukaemia, and would no longer contribute to the future development of Komodo.^[9] On October 8, Don made an announcement on the Talkchess forum that Mark Lefler would be joining the Komodo team and would continue its development.^[10]

On December 17, 2018, Larry Kaufman announced the release of Komodo 12.3 MCTS, a version of the Komodo 12.3 engine that uses Monte Carlo tree search instead of alpha–beta pruning/minimax.^[11]

The latest version, Komodo Dragon 2.5, was released on September 24, 2021.^[12] It features support for NNUE.^[13]

Playing strength and style[]

Komodo heavily relies on evaluation rather than depth, and thus has a distinctive positional style. Its forte is to play when there is nothing to play.^[14] Komodo author Don Dailey described it as such: "In positions that most engines would likely struggle or find it impossible to make progress, Komodo quietly prepares a break and ends up with the victory."^[15]

Competition results[]

Komodo has played in the ICT 2010 in Leiden, and further in the CCT12 and CCT14. Komodo had its first tournament success in 2013, when it won the CCT15 with a score of 6½/7.^[16] Komodo also fared very well in the TCEC competition, where in Season 4, it lost only eight out of its 53 games and managed to reach Stage 4 (Quarterfinals), against very strong competition which were running on eight cores (Komodo was running on a single processor).^[17] In TCEC Season 5, it won the superfinal against Stockfish. It managed to reach the Superfinal in TCEC Season 6 again, but this time, it lost to Stockfish. Komodo regained the title in TCEC Season 7, defeating Stockfish in the superfinal. In TCEC Season 8, Komodo defeated Stockfish again in the superfinal.^[18] Komodo won both the World Computer Chess Championship^[19] and World Computer Software Championship^[20] in 2016. Komodo once again won the World Computer Chess Championship^[21] and World Blitz^[22] in 2017. Komodo came third in TCEC Season 11 losing to Stockfish and Houdini, and came second in Season 12 losing to Stockfish.^[23][24][25]

Notable games[]

Komodo vs Hannibal

	a	b	c	d	e	f	g	h
8									8
7									7
6									6
5									5
4									4
3									3
2									2
1									1
	a	b	c	d	e	f	g	h

Komodo plays the exchange sacrifice 33. Rxc6 and goes on to win the game, proving the superiority of its pieces over Black's two rooks.

• Komodo vs Hannibal, nTCEC - Stage 2b - Season 1, Round 4.1, ECO: A10, 1–0 Komodo sacrifices an exchange for positional gain.^[26]
• Gull vs Komodo, nTCEC - Stage 3 - Season 2, Round 2.2, ECO: E10, 0–1^[26][27]

References[]

External links[]

• Official website