Technical Features

More information about the algorithms used in this project can be found on the Chess programming wiki

• Engine compatible with UCI and CECP protocols
• Bitboards and magic bitboards
• alpha-beta search (negamax)
• Principal Variation Search
• Quiescence search
• Iterative deepening
• Aspiration window
• Opening book (Polyglot format)
• Internal iterative deepening
• Adaptive null moves pruning
• Late move reduction
• Late move pruning
• Futility pruning
• Razoring
• Mate distance pruning
• Multiple threads support
  • Young Brother Wait Concept (YBWC)
    • Support 64 threads maximum
  • "Lazy SMP" (Shared hash table)
    • Support 256 threads maximum in Linux, and 64 in Windows
• Transposition table + Zobrist hash key
  • Use Mersenne Twister for random numbers
  • 4 buckets
  • Replacement scheme : use age and depth
• Pawn Hash table (2 Mb)
• Search extensions
  • Check extension
  • Pawn on 7th
• Evaluation function
  • Lazy evaluation
  • Game phase (incremental)
  • Material (incremental)
  • Mobility tables
  • Piece square tables
  • Doubled pawns
  • Passed pawns
  • Isolated pawns
  • Backward pawns
  • Blocked pawns
  • Rooks on open or semi-open files
  • Rooks on 7th rank
  • King safety
  • Knight outposts
  • Insufficient Material
  • Endgames
  • Allow to change some parameters with personalities
  • Texel's tuning method
    • Gradient descent algorithm
• Tablebases
  • Syzygy tablebases
• Move ordering
  • Hash table
  • SEE good captures and promotions
  • Killer moves
  • Counter moves
  • History heuristic
  • SEE bad captures
• Rules
  • Standard
  • FRC