Flying Fish

Alpha-beta pruning chess engine, using bitboards + hyperbola quintessence. Currently ~1500 ELO (relative to CCRL 40/15).

Performance

Perft: measures move generation + move make/unmake (cargo bench -p engine -- perft)

• Non-bulk, single-threaded: 55.6M positions/second (M4 Pro)

Features

Board representation + move generation

• Bitboards
• Hyperbola quintessence
• Zobrist hashing

Search

• Minimax
• Alpha-beta pruning
• Iterative deepening
• Quiescence search
• Transposition table
• Basic move ordering: transposition table move and MVV-LVA
• Principal variation search
• Null move pruning

Evaluation

• Pieces value
• Piece square table
• Tapered eval

How to run

To build the UCI binary:

cargo build -p cli --release

then start by running the binary with no arguments.

Notes

Tricky move generation bugs I encountered found:

• En passant pinning
• A pawn that can be en passant'd is checking the king
• A piece that is pinned can move to block/capture a checker