Thank you

Credits & licences

PHG Labs Play is built on excellent free and open-source work:

• Stockfish 19: the chess engine behind Play the Computer, compiled to WebAssembly by stockfish.js. Licensed under the GNU General Public License v3 (full licence). The complete source code is available at github.com/nmrugg/stockfish.js and github.com/official-stockfish/Stockfish. We use it unmodified.
• chess.js: chess rules and move validation, BSD-2-Clause licence (licence, source).
• cm-chessboard: the chessboard and pieces, MIT licence (licence, source).
• Lichess puzzle database: the chess puzzles, released under CC0 (public domain) by lichess.org.
• Inter: the typeface, by Rasmus Andersson, SIL Open Font License, served by Google Fonts.

All other games, puzzles, questions and explanations are original work by PHG Labs.