fastchess
A high-performance chess library written in C with Python bindings. Designed as a fast drop-in replacement for python-chess in data pipelines and machine learning workflows.
Installation
pip install fastchess
Requires a C compiler and NumPy. On most systems pip will handle this automatically.
Usage
import fastchess
board = fastchess.Board() # start position
board = fastchess.Board("rnbqkbnr/...") # from FEN
# Move generation
moves = board.legal_moves_uci() # ['e2e4', 'd2d4', ...]
# Apply moves
board.push_uci("e2e4")
board.push_san("e5")
# Board state
print(board.fen())
print(board.turn) # fastchess.WHITE or fastchess.BLACK
print(board.is_check())
# Tensor for ML (18 x 8 x 8 numpy array)
tensor = board.to_tensor(canonical=True)
# Mirroring
mirrored = board.mirror()
API
fastchess.Board(fen=None)
| Method | Description |
|---|---|
copy() |
Return a copy of the board |
mirror() |
Return a vertically mirrored copy with swapped colors |
push_uci(uci) |
Apply a UCI move (e.g. "e2e4") |
push_san(san) |
Apply a SAN move; returns the UCI string |
legal_moves_uci() |
List all legal moves as UCI strings |
piece_at(sq) |
(piece_type, color) at square index, or None |
is_check() |
True if the side to move is in check |
has_kingside_castling_rights(color) |
Castling rights query |
has_queenside_castling_rights(color) |
Castling rights query |
has_legal_en_passant() |
True if a legal en passant capture exists |
to_tensor(canonical=False) |
Board as (18, 8, 8) numpy array |
fen() |
Current FEN string |
Constants
WHITE, BLACK, PAWN, KNIGHT, BISHOP, ROOK, QUEEN, KING
License
MIT
1 maintainer
Release files for fastchess 0.1.2
For a detailed explanation of source distributions (sdists) and built distributions (wheels), please see the package formats documentation.
Source distribution (sdist)
| File | Size | Uploaded | |
|---|---|---|---|
| fastchess-0.1.2.tar.gz | 13.3 kB | Details |
Built distributions (wheels)
| File | Reset | |||
|---|---|---|---|---|
| fastchess-0.1.2-cp312-cp312-win_amd64.whl | CPython 3.12 | CPython 3.12 | Windows x86-64 | Details |
| fastchess-0.1.2-cp312-cp312-macosx_11_0_arm64.whl | CPython 3.12 | CPython 3.12 | macOS 11.0+ ARM64 | Details |
| fastchess-0.1.2-cp311-cp311-win_amd64.whl | CPython 3.11 | CPython 3.11 | Windows x86-64 | Details |
| fastchess-0.1.2-cp311-cp311-macosx_11_0_arm64.whl | CPython 3.11 | CPython 3.11 | macOS 11.0+ ARM64 | Details |
| fastchess-0.1.2-cp310-cp310-win_amd64.whl | CPython 3.10 | CPython 3.10 | Windows x86-64 | Details |
| fastchess-0.1.2-cp310-cp310-macosx_11_0_arm64.whl | CPython 3.10 | CPython 3.10 | macOS 11.0+ ARM64 | Details |
| fastchess-0.1.2-cp39-cp39-win_amd64.whl | CPython 3.9 | CPython 3.9 | Windows x86-64 | Details |
| fastchess-0.1.2-cp39-cp39-macosx_11_0_arm64.whl | CPython 3.9 | CPython 3.9 | macOS 11.0+ ARM64 | Details |
Total release size: 151.2 kB
Release files / fastchess-0.1.2.tar.gz
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