It’s been a while since I’ve posted any chess, and development in the engine world has continued apace, so it was time to see how they do with Douglas Modern Chess.

I consulted recent events at https://www.tcec-chess.com/ as well as the rankings at https://ccrl.chessdom.com/ccrl/4040/ and selected the following engines to compete:

Bezerk
Stockfish 15
Ethereal
SlowChess 2.83
Koivisto_8.9
RubiChess
PeSTO
rofChade
Seer
arasanx-64
zahak
Igel
velvet-v3.3.0

Pesto was not one of the top engines, it’s new, from the rofChade team, so I thought I would include it. I did try to add LC0, Cute Chess loaded it, but they still won’t talk to each other so there is still something wrong with my installation.

Initial rounds were round-robin and run at short time controls (3 min + 5 seconds, slowly adding 1 minute for each succeeding round).

The first two rounds eliminated all except Stockfish, AransanX, Bezerk, Seer, Koivisto, and rofChade.

The next rounds eliminated rofChade, then Seer and AransanX, leaving only Stockfish, Bezerk, and Koivisto.

Bezerk then fell out, leaving Stockfish and Koivisto to battle it out in the finals. I then made a change to the starting position, swapping the black king and queen, so that both sides now have identical starting positions, with the queen on the left of the king. The rationale is to try and minimise white’s inherent advantage.

The final was 10 games with time control 30 minutes + 15 seconds. I did notice that the engines played better as the time controls got longer. However, they still all tend to struggle with the pawn/bishop/knight end-games, and pawn blockades.

The final result by conventional scoring was:

Engine            		Win	Draw	Lose
Koivisto_8.9             	0 [0/0]	7 [5/2]	3 [0/3]
Stockfish-15-Official     	3 [3/0]	7 [2/5]	0 [0/0]

Cute Chess scoring:

Stockfish-15-Official 	: 322	: 64.4 %
Koivisto_8.9 		: 172	: 34.4 %

My scoring:

Stockfish-15-Official : 7.88
Koivisto_8.9          : -8.54

Koivisto did well. Stockfish was unable to win when black, and only managed one mate as white. The other two wins were adjudicated. Here’s the mate game.