New engine releases & news H1 2026

[Frank Quisinsky]

RuthIron 18.9.9
https://github.com/themreKalkan/RuthIron
by Emre Kalkan, Turkey

[lithander]

Leorik 3.2.1
https://github.com/lithander/Leorik/releases/tag/3.2
by Thomas Jan, Germany

The new version fixes a bug with the undodumented Temperature UCI option. It makes the engine have random biases towards root moves and is great for selfplay data generation or when you want to limit the playing strength. For everybody maintaining a rating list this version should behave exactly like 3.2!

[CJDC]

Greetings,

Yakka v1.5 released.

Strength gain due to bigger NNUE net and improvements.

https://github.com/CJDalrymple/Yakka

Regards to all.

[GyatsoYT]

Gyatso v1.2.0 is now available.
https://github.com/GyatsoYT/GyatsoChess ... tag/v1.2.0

Estimated strength around ~2700 Elo based on current testing, though further evaluation is appreciated.

— Gyatso

[Andres Valverde]

Caligula 4.0 released

https://sites.google.com/view/dirtychess/dirtychess

Major change in NN calling management
NN is the same (2.0.1)
Thx to David Carteau (Cerebrum) and Jim Ablett (his complies are included)

[ranzuh]

Introducing new chess engine from Finland. Ratsu is alpha-beta based 0x88 board engine written in rust. I estimate its strength to be around 1800-1900 Elo CCRL blitz. Author is me, Eetu Rantala. The source code is here: https://github.com/ranzuh/ratsu and the release with binaries is here: https://github.com/ranzuh/ratsu/releases/tag/v0.9.0. It's also playing on lichess at https://lichess.org/@/ratsu-bot

[Andres Valverde]

Caligula 5.0 released

https://sites.google.com/view/dirtychess/dirtychess

No changes in J.A. EXEs (only version name)
New NN 2.0.3

[ChickenMan4236]

Introducing my UCI engine - Zeppelin v1.0.0 from Poland

https://github.com/jszczerbinsky/zeppel ... tag/v1.0.0
http://zeppelin.bot.nu/

v1.0.0 release brings NNUE evaluation

Support for x86_64bit on Windows and Linux, and ARM_64bit on Linux

[ChickenMan4236]

New release: Zeppelin v1.1.0
https://github.com/jszczerbinsky/zeppel ... tag/v1.1.0

[Damir]

NikolaChess: https://github.com/star-ga/NikolaChess/ ... ag/v3.21.0