Source Code

Lichess is free/libre open source software. You can download, read, use and modify every bit of source code.

Main server

• ornicar/lila Main backend and frontend
• ornicar/lila modules Backend modules
• ornicar/lila ui Frontend modules
• ornicar/scalachess Rules of chess and its variants
• lichess/compression Compression algorithms for chess moves and clocks
• ornicar/chessground Frontend chess board
• ornicar/lila-ws Reduces load on the main server by handling some (non-gameplay) websockets
• niklasf/stockfish.js, niklasf/stockfish.wasm, niklasf/stockfish.pexe Latest Stockfish compiled for browsers

External services

• ornicar/lila-search Search engine
• niklasf/lila-openingexplorer Opening explorer
• niklasf/lila-tablebase Tablebase
• niklasf/lila-push Web Push service
• niklasf/fishnet Distributed computer analysis, using Multi-Variant Stockfish
• niklasf/web-boardimage Board thumbnail images
• ornicar/lichess-oauth-server OAuth server
• clarkerubber/irwin AI that learns cheating patterns to help mods

Mobile app

• veloce/lichobile Main mobile app
• veloce/scalachessjs Rules of chess and its variants
• veloce/cordova-plugin-stockfish Cordova interface Stockfish

Docs & utilities

• lichess/api HTTP API documentation (read here)
• ornicar/lichess-puzzle-kit Get started with hacking Lichess puzzles
• ornicar/jquery Trimmed down jQuery fork
• ornicar/lichess-db Generator for database.lichess.org (download all rated games)
• careless25/lichess-bot Bridge between HTTP API and chess engines

Happy coding!