Credits and sources

Chess pieces

The unmodified Cburnett SVG pieces are by Colin M. L. Burnett, from the Lichess piece collection, under CC BY-SA 3.0. This license applies to the pieces independently of Knightly.

Rules, puzzles and game scores

Rules use chess.js by Jeff Hlywa and contributors (BSD-2-Clause). Selected puzzle positions and opening data come from Lichess CC0 collections. Historical move scores are attributed in sessions. Knightly’s training text is original.

Analysis

The browser trainer uses Knightly’s smaller local practice engine. Native builds use Stockfish17.1 under GPLv3 or later, with official CC0 evaluation networks. The website does not distribute the native engine.

Software notices

The interface uses React, React Native Web, Expo and Lucide. Read the bundled software notices.

Independent product

Knightly is not affiliated with Chess.com, Duolingo or Lichess.