RubiChess – chess engine written in C++

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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