Combusken
Combusken,
an UCI compliant open source chess engine by Marcin Henryk Bartkowiak, written in the Go programming language, first released in February 2020 under the GPL 3 [1].
Already playing since April 2019 at Lichess [2], it had its tournament debut at TCEC Season 18.
Contents
Features
Board Representation
Search
- Lazy SMP
- Iterative Deepening
- Aspiration Windows
- Alpha-Beta
- Transposition Table
- Selectivity
- Move Ordering
Evaluation
- Tapered Eval
- Material
- Bishop Pair
- Piece-Square Tables
- Mobility
- Outposts
- Rook on (Half) Open File
- Pawn-King Hash Table
- Pawn Structure
- King Safety
- Hanging Pieces
- Tempo
- Automated Tuning using Gradient Descent
Misc
- Syzygy Bases using Fathom
- Perft
Thanks
The author mentions following engines and their authors for implementation details and tuning positions [5]:
- CounterGo by Vadim Chizhov
- Ethereal by Andrew Grant
- Laser by Jeffrey An
- Stockfish by Tord Romstad, Marco Costalba, Joona Kiiski and Gary Linscott
- Zurichess by Alexandru Mosoi
Forum Posts
- Re: New engine releases 2020 by Marcin Henryk Bartkowiak, CCC, February 23, 2020
- Re: New engine releases 2020 by Marcin Henryk Bartkowiak, CCC, April 06, 2020
- Re: New engine releases 2020 by Marcin Henryk Bartkowiak, CCC, October 31, 2020
- Re: Faster compiles for Intel possible for Booot & Combusken? by Marcin Henryk Bartkowiak, CCC, November 21, 2020