Sources and licenses
Everything the coach says is written for 64Coach. Positions, moves and opening names are facts that anyone may use; this page lists where ours come from, and the software the app runs on.
Puzzles
33,557 rated puzzles come from the Lichess puzzle database, which is in the public domain (CC0). We picked popular ones and spread them across ratings and themes.
The classic combinations come from famous games of the old masters. A game's moves are facts; each score was checked against a published record, and Stockfish checked every move of the puzzles.
The 36 games
- Kermur de Légal vs Saint Brie, Paris 1750
- Alexander McDonnell vs Louis de La Bourdonnais, London 1834
- Adolf Anderssen vs Lionel Kieseritzky, London 1851
- Adolf Anderssen vs Jean Dufresne, Berlin 1852
- Schulder vs Samuel Boden, London 1853
- Louis Paulsen vs Paul Morphy, New York 1857
- Paul Morphy vs Duke of Brunswick and Count Isouard, Paris 1858
- Johannes Zukertort vs Adolf Anderssen, Breslau 1865
- Johannes Zukertort vs Wilhelm Steinitz, New York (World Championship, game 5) 1886
- Johannes Zukertort vs Wilhelm Steinitz, New York (World Championship, game 7) 1886
- Johannes Zukertort vs Wilhelm Steinitz, New Orleans (World Championship, game 19) 1886
- Wilhelm Steinitz vs Johannes Zukertort, New Orleans (World Championship, game 20) 1886
- Emanuel Lasker vs Johann Bauer, Amsterdam 1889
- Mikhail Chigorin vs Wilhelm Steinitz, Havana (World Championship, game 5) 1889
- Mikhail Chigorin vs Wilhelm Steinitz, Havana (World Championship, game 1) 1889
- Mikhail Chigorin vs Wilhelm Steinitz, Havana (World Championship, game 13) 1889
- Mikhail Chigorin vs Wilhelm Steinitz, Havana (World Championship, game 7) 1889
- Wilhelm Steinitz vs Mikhail Chigorin, Havana (World Championship, game 14) 1889
- Wilhelm Steinitz vs Mikhail Chigorin, Havana (World Championship, game 16) 1889
- Wilhelm Steinitz vs Mikhail Chigorin, Havana (World Championship, game 10) 1889
- Wilhelm Steinitz vs Mikhail Chigorin, Havana (World Championship, game 8) 1889
- Mikhail Chigorin vs Wilhelm Steinitz, Havana (World Championship, game 23) 1892
- Mikhail Chigorin vs Wilhelm Steinitz, Havana (World Championship, game 19) 1892
- Mikhail Chigorin vs Wilhelm Steinitz, Havana (World Championship, game 1) 1892
- Mikhail Chigorin vs Wilhelm Steinitz, Havana (World Championship, game 7) 1892
- Mikhail Chigorin vs Wilhelm Steinitz, Havana (World Championship, game 13) 1892
- Mikhail Chigorin vs Wilhelm Steinitz, Havana (World Championship, game 17) 1892
- Wilhelm Steinitz vs Mikhail Chigorin, Havana (World Championship, game 22) 1892
- Wilhelm Steinitz vs Mikhail Chigorin, Havana (World Championship, game 4) 1892
- Wilhelm Steinitz vs Mikhail Chigorin, Havana (World Championship, game 6) 1892
- Wilhelm Steinitz vs Curt von Bardeleben, Hastings 1895
- Gersz Rotlewi vs Akiba Rubinstein, Łódź 1907
- Richard Réti vs Savielly Tartakower, Vienna 1910
- Edward Lasker vs George Thomas, London 1912
- Stepan Levitsky vs Frank Marshall, Breslau 1912
- Carlos Torre vs Emanuel Lasker, Moscow 1925
Openings and lessons
The 36 opening lines, the notes on their moves and all 41 lessons are written by 64Coach. Every position and move is checked with chess.js and Stockfish.
Software
- Stockfish 18, the engine, through stockfish.js. GNU General Public License v3 (license text). The source code is at github.com/official-stockfish/Stockfish and github.com/nmrugg/stockfish.js.
- chess.js, the rules of chess. BSD 2-Clause License.
- cm-chessboard, the board. MIT License.
- The pieces are by Cburnett and Rfc1394 on Wikimedia Commons, adapted by shaack. CC BY-SA 3.0.
- Bootstrap, the page layout. MIT License.