woodpusher

(chess, informal, derogatory) A bad player; an amateur.

A more or less UCI-compatible chess engine. Plug it into your favourite GUI.

Features

• UCI-compatible
• PGN and FEN parsing
• Perft test
• Opening book
• Zobrist hashing
• Transposition table
• Killer heuristic

UCI Commands

uci

Initializes the engine and provides engine information.

Arguments:

• None

Example:

uci
id name Woodpusher 1.3.0+297f7e61aacf60753d108e72544b141ccbc6ecd5
id author Mikael Fredriksson <[email protected]>
option name OwnBook type check default true
uciok

setoption

Sets an engine option.

Arguments:

• name <option_name>: The name of the option.
• value <option_value>: The value of the option.

Example:

setoption name OwnBook value false

isready

Checks if the engine is ready.

Arguments:

• None

ucinewgame

Initializes a new game.

Arguments:

• None

position

Sets up the board position using FEN and optional moves.

Arguments:

• fen <fen_string>: Sets the board position using the provided FEN string.
• moves <move1> <move2> ...: A list of moves in algebraic notation to be played from the given position or the starting position if no FEN is provided.

Example:

position fen rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1 moves e2e4 e7e5

go

Starts the engine to find the best move or perform a perft test.

Arguments:

• wtime <milliseconds>: White's remaining time in milliseconds.
• btime <milliseconds>: Black's remaining time in milliseconds.
• movestogo <number>: Number of moves to the next time control.
• movetime <milliseconds>: Time to search in milliseconds.
• perft <depth>: Perform a perft test to the given depth.

Example:

go wtime 300000 btime 300000 movestogo 40
info string debug playing opening book g1f3
bestmove g1f3

stop

Stops the engine's current calculation.

Arguments:

• None

d

Displays the current board position.

Arguments:

• None

Example:

d
8 r n b q k b n r
7 p p p p · p p p
6 · · · · · · · ·
5 · · · · p · · ·
4 · · · · P · · ·
3 · · · · · · · ·
2 P P P P · P P P
1 R N B Q K B N R
  a b c d e f g h
Hash: 6805972066694293741
FEN: rnbqkbnr/pppp1ppp/8/4p3/4P3/8/PPPP1PPP/RNBQKBNR w KQkq e6 0 2

quit

Exits the engine.

Arguments:

• None

Win vs. Stockfish 15 in ultra bullet

To be fair, I've let them play hundreds of games, and this is the only one where Woodpusher won. It's a very rare event and probably due to the phase of the moon or something.

[Event "?"]
[Site "?"]
[Date "2024.11.08"]
[Round "?"]
[White "Woodpusher (release)"]
[Black "stockfish_15_x64_avx2"]
[Result "1-0"]
[ECO "B29"]
[GameDuration "00:00:28"]
[GameEndTime "2024-11-08T22:11:39.397 W. Europe Standard Time"]
[GameStartTime "2024-11-08T22:11:10.518 W. Europe Standard Time"]
[Opening "Sicilian"]
[PlyCount "85"]
[TimeControl "40/15"]
[Variation "Nimzovich-Rubinstein Variation"]

1. e4 c5 {-0.26/21 1.8s} 2. Nf3 Nf6 {-0.21/14 0.22s} 3. e5 Nd5 {-0.49/17 0.93s}
4. Nc3 e6 {-0.46/15 0.45s} 5. Nxd5 exd5 {-0.39/16 0.55s} 6. d4
cxd4 {-0.28/13 0.24s} 7. Nxd4 {+0.16/2 0.084s} Qb6 {-0.87/16 1.1s}
8. c3 {-0.83/4 0.35s} Bc5 {-0.59/13 0.34s} 9. b4 {-0.59/4 0.36s}
Bxd4 {-0.16/14 0.47s} 10. Qxd4 {-0.15/4 0.36s} O-O {-0.46/15 0.49s}
11. Bd3 {-0.18/4 0.36s} Re8 {-0.40/13 0.23s} 12. Be3 {-0.12/4 0.37s}
Qe6 {-1.21/16 0.58s} 13. O-O {+0.02/2 0.37s} d6 {-2.82/19 1.2s}
14. Qh4 {+0.02/4 0.37s} h5 {-2.72/17 1.1s} 15. Qxh5 {+0.96/4 0.39s}
g6 {-4.02/16 0.35s} 16. Qg5 {+0.44/4 0.38s} d4 {-2.30/15 0.40s}
17. cxd4 {+1.59/4 0.39s} a6 {-5.62/17 0.84s} 18. Qh6 {+1.84/4 0.39s}
b5 {-4.85/14 0.33s} 19. Be4 {+2.04/4 0.39s} Ra7 {-8.18/16 0.65s}
20. Rfe1 {+2.31/4 0.41s} d5 {-8.19/15 0.53s} 21. Bf3 {+2.06/4 0.41s}
Rb7 {-8.80/14 0.43s} 22. a4 {+2.24/4 0.41s} Rb6 {-8.66/12 0.14s}
23. axb5 {+2.68/4 0.42s} Rxb5 {-8.71/14 0.33s} 24. Rac1 {+1.99/4 0.42s}
Bd7 {-7.12/14 0.26s} 25. Rc7 {+1.92/4 0.42s} Nc6 {-8.30/13 0.21s}
26. Be2 {+1.69/4 0.43s} Rbb8 {-5.54/12 0.096s} 27. Bxa6 {+1.96/4 0.44s}
Nxb4 {-3.52/12 0.14s} 28. Be2 {+1.95/4 0.44s} Rec8 {-8.17/13 0.12s}
29. Rec1 {+1.89/4 0.46s} Rxc7 {-5.15/11 0.051s} 30. Rxc7 {+1.75/4 0.46s}
Nc2 {-4.87/12 0.079s} 31. Rxc2 {+2.03/4 0.47s} Ba4 {-7.82/11 0.061s}
32. Rc1 {+4.46/4 0.48s} Qb6 {-9.05/10 0.048s} 33. Bg4 {+4.76/4 0.49s}
Qb1 {-10.37/9 0.035s} 34. Rxb1 {+6.50/4 0.51s} Rxb1+ {-10.67/9 0.028s}
35. Bc1 {+7.82/6 0.36s} Bb3 {-10.18/8 0.023s} 36. e6 {+9.40/4 0.14s}
Rxc1+ {-10.76/9 0.022s} 37. Qxc1 {+11.64/6 0.41s} f5 {-11.16/9 0.020s}
38. Bf3 {+12.36/4 0.27s} Bc2 {-24.82/9 0.020s} 39. Qxc2 {+16.07/6 0.54s}
Kf8 {-M12/16 0.017s} 40. Qc7 {+16.99/6 0.20s} Kg8 {-M6/81 0.011s}
41. Qf7+ {+M5/6 0.22s} Kh8 {-M4/245 0.004s} 42. e7 {+M3/4 0.022s}
g5 {-M2/245 0.003s} 43. e8=Q# {+M1/2 0.010s, White mates} 1-0