Lila
About this project
Lila (li[chess in sca]la) is a free online chess game server focused on realtime gameplay and ease of use.
It features a search engine, computer analysis distributed with fishnet, tournaments, simuls, forums, teams, tactic trainer, a mobile app, and a shared analysis board. The UI is available in more than 140 languages thanks to the community.
Lichess is written in Scala 3, and relies on the Play 2.8 framework. scalatags is used for templating. Pure chess logic is contained in the scalachess submodule. The server is fully asynchronous, making heavy use of Scala Futures and Akka streams. WebSocket connections are handled by a separate server that communicates using redis. Lichess talks to Stockfish deployed in an AI cluster of donated servers. It uses MongoDB to store more than 4.7 billion games, which are indexed by elasticsearch. HTTP requests and WebSocket connections can be proxied by nginx. The web client is written in TypeScript and snabbdom, using Sass to generate CSS. All rated games are published in a [free PGN database](http