Licensing and credits¶
Bundling Stockfish (GPLv3) and the cburnett piece set (GPLv2+) makes this application GPLv3.
Bundled software¶
Stockfish — the engine, GPLv3.
lichess — piece sets, sound sets, the game export API and the endgame tablebase. Board interaction is informed by Chessground.
Opening names and lines from lichess chess-openings, CC0.
Piece sets¶
Credited one by one in assets/piece/CREDITS.md, alongside the upstream
assets/piece/LICHESS-COPYING.md and the bundled licence texts. py tools/fetch_pieces.py
refreshes them.
Two carry conditions worth knowing before you redistribute this repository:
Alpha (Eric Bentzen) — free for personal, non-commercial use only.
Maestro (sadsnake1) — CC BY-NC-SA 4.0.
Cburnett, Merida, Chessnut, Fantasy, Celtic, Spatial and Rhos are free software or public domain.
Sound sets¶
Credited in assets/sound/CREDITS.md, taken from lila’s own COPYING.md.
Set |
Author |
Licence |
|---|---|---|
standard, robot, woodland |
the lila authors |
AGPLv3+ |
piano, sfx, futuristic, nes |
Enigmahack |
AGPLv3+ |
lisp |
EdinburghCollective |
CC BY-NC-SA 4.0 |
Take care
chess.com’s sounds are not redistributable. They are proprietary, and nothing in this repository ships them.
tools/fetch_sounds.py --chesscomdownloads them toassets/sound/chesscom/on your own machine, where.gitignoreandcaissa.speckeep them out of the repository and out of any build. Use them for your own study; do not pass them on.
The Caissa wood and Caissa digital presets are synthesized in js/sounds.js and
are part of this project.
Services used, not copied¶
Chess Tempo — tactics, used through their own site in an embedded window.
Wikipedia — summaries on the Facts tab, quoted with links to the source.
The Week in Chess and PGN Mentor — freely published PGN collections, downloaded on request.
Exercises¶
The blindfold curriculum follows AdviceCabinet’s 7 Levels of Blindfold Chess Exercises for Everyone.