Open-source acknowledgements
ChessCoda stands on outstanding open-source chess software. The components below run as separate server-side programs, at arm's length from our own code, and we gratefully credit the people who build them.
Stockfish GPL-3.0
The strongest open-source chess engine, used for position evaluation and best-move analysis. Stockfish runs server-side as a separate engine process, communicating over the standard UCI protocol.
Maia (Maia Chess, by CSSLab at the University of Toronto) AGPL-3.0
A neural-network chess model trained to predict how human players of different strengths actually play. ChessCoda runs Maia server-side as a separate UCI process via a published open-source wrapper; it is never linked into our application code.
Lichess open puzzle database CC0 (public domain)
Practice puzzles in ChessCoda are derived from the freely published Lichess puzzle database.
The ChessCoda Coach Engine
The ChessCoda platform and the ChessCoda Coach Engine, the technology that turns engine analysis into personal coaching, are proprietary software owned by ChessCoda. They are not derived from the open-source components above and are not covered by their licenses. Stockfish and Maia are independent projects; their mention here is attribution, not endorsement.