RubiChess is a very strong UCI-compliant chess engine. The Universal Chess Interface (UCI) is an open communication protocol that enables chess engines to communicate with user interfaces.
This engine started in 2016 as a private hobby project to practise programming in C++ and to see the engine improving compared to earlier releases.
RubiChess is published under an open source license.
Features include:
- Uses magic bitboards (about 24% faster than rotated bitboards) to determine sliding piece attacks.
- Search functionality:
- Lazy SMP (1.3).
- Iterative Deepening.
- Aspiration Windows.
- Alpha-Beta.
- Principal Variation Search.
- Transposition Table.
- Selectivity:
- Null Move Pruning with Verification.
- Late Move Reductions.
- ProbCut (1.3).
- Futility Pruning.
- Extended Futility Pruning.
- Late Move Pruning.
- Reverse Futility Pruning.
- Razoring.
- Singular Extensions.
- Quiescence Search.
- SEE Pruning.
- Delta Pruning.
- Move Ordering:
- PV-Move.
- Internal Iterative Deepening.
- Captures by MVV/LVA.
- Static Exchange Evaluation.
- Killer Heuristic.
- History Heuristic.
- Counter Moves History.
- Evaluation:
- NNUE (RubiChess NNUE).
- Texel’s Tuning Method.
- Tapered Eval.
- Material.
- Piece-Square Tables.
- Mobility.
- Rooks on (Semi) Open Files.
- Hanging Pieces.
- Pinned Pieces.
- Pawn/King Hash Table.
- Pawn Structure:
- Phalanx.
- Passed Pawn.
- Candidate Passed Pawn.
- King Safety:
- Attacks.
- Pawn Storm.
- Tempo Bonus.
Website: github.com/Matthies/RubiChess
Support:
Developer: Andreas Matthies
License: GNU General Public License v3.0
RubiChess is written in C++. Learn C++ with our recommended free books and free tutorials.
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