Lunar 0.4.0 - new version chess engine

Lunar - UCI chess engine

Author: Patrick Hilhorst

Lunar 0.4.0 - what's new in this version?

Lunar 0.4.0 is out! Strength increases due to:

Larger net (from 512 to 1024)

Various speedups (though overall nps is lower due to the larger net)

Correction history

Some bugfixes

Lunar 0.4.0 - Playing strength?

Roughly 3500 CCRL Blitz. Results on the progress tests were a bit mixed (and I did fewer than last time), so error bars are fairly large here. so please don't hurt me if this estimate is a bit off 😔

+136 Balanced book STC vs lunar 0.3.0

Elo   | 136.46 +- 7.69 (95%)

Conf  | 8.0+0.08s Threads=1 Hash=64MB

Games | N: 4000 W: 1801 L: 306 D: 1893

Penta | [9, 135, 598, 868, 390]

https://synthetica.eu.pythonanywhere.com/test/373/

+155 Balanced book LTC vs lunar 0.3.0

Elo   | 155.61 +- 10.11 (95%)

Conf  | 40.0+0.40s Threads=1 Hash=128MB

Games | N: 2004 W: 899 L: 57 D: 1048

Penta | [1, 21, 316, 463, 201]

https://synthetica.eu.pythonanywhere.com/test/374/

-55 Balanced book LTC vs Halogen 12

Elo   | -56.25 +- 8.39 (95%)

Conf  | 40.0+0.40s Threads=1 Hash=128MB

Games | N: 2000 W: 198 L: 519 D: 1283

Penta | [55, 326, 510, 103, 6]

Lunar 0.2.1 vs other engines:

Ironfang 1.0	2/4	+0	4 Games
Kraken 2025-06-16	2/3	+1	3 Games
Fridolin 4.00 JA	1.5/3	+0	3 Games
Libra-chess 1.0.1	2/2	+2	2 Games
Maelstrom 2.1.0	2/2	+2	2 Games
Aku 2025.6.12 JA	2/2	+2	2 Games
Freda 1.1	2/2	+2	2 Games
Emerald 0.3.0	2/2	+2	2 Games
Celeris 1.0	1.5/2	+1	2 Games
Pzchessbot 2.0	1/2	+0	2 Games
Stormphrax 7.0.0	0.5/2	-1	2 Games
Fire 9.3 JA	0.5/2	-1	2 Games
Zangdar 4.04	0/2	-2	2 Games
Zangdar 4.04 JA	0/2	-2	2 Games
Fire 10	0/2	-2	2 Games
PlentyChess 6.0.5 JA	0/2	-2	2 Games
Halogen 13	0/2	-2	2 Games
Razer 0.0 JA	0/2	-2	2 Games
Aku 2025.22.5 JA	0/2	-2	2 Games
PZChessBot 2.0 JA	0/2	-2	2 Games
Critter 1.6a	0/1	-1	1 Games

Lunar 0.4.0 download