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lila

♞ lichess.org: the forever free, adless and open source chess server ♞. Read more below about its uses, features, and usage.

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git clone https://github.com/lichess-org/lila.git

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lichess.org

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Lichess homepage

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 a modified 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 Pekko 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 12 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. Browser testing done with Browserstack. Proxy detection done with IP2Proxy database. Please help us translate Lichess with Crowdin.

See lichess.org/source for a list of repositories.

Join us on Discord for more info. Use GitHub issues for bug reports and feature requests.

Installation

./lila.sh # thin wrapper around sbt
run

The Wiki describes how to setup a development environment.

HTTP API

Feel free to use the Lichess API in your applications and websites.

Supported browsers

Name Version Notes
Firefox 115+ Full support (recommended)
Chromium / Chrome 112+ Full support
Edge 111+ Full support
Opera 97+ Reasonable support
Safari 16.2+ Reasonable support

Older browsers will not work. For your own sake, please upgrade. Security and performance, think about it!

License

Lila is licensed under the GNU Affero General Public License 3 or any later version at your choice. See copying for details.

Production architecture (as of July 2022)

Lichess production server architecture diagram

Credits

See lichess.org/thanks and the contributors here:

GitHub contributors

Competence development program

Lichess would like to support its contributors in their competence development by covering costs of relevant training materials and activities. This is a small way to further empower contributors who have given their time to Lichess and to enable or improve additional contributions to Lichess in the future. For more information, including how to apply, check Competence Development for Lichess contributors.

Releases

Aug 31, 2017

lichess 1.1

Download .zip

Uptime: 1 week. Last release on scala 2.11 and Play 2.4.

Jan 8, 2017

lichess 1.0

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✨ First release of lichess stable ✨ It ran 9 days without a restart. No measurable memory leak. About 8 million games were played during this time lapse. That's roughly 480 million moves. Known defe...

Contributors

ornicar avatar ornicar 60,115 commits niklasf avatar niklasf 3,113 commits jonbgamble avatar jonbgamble 2,870 commits lenguyenthanh avatar lenguyenthanh 971 commits benediktwerner avatar benediktwerner 944 commits kraktus avatar kraktus 805 commits johndoknjas avatar johndoknjas 670 commits fitztrev avatar fitztrev 662 commits scala-steward avatar scala-steward 657 commits isaacl avatar isaacl 647 commits

300 contributors by commits. Profile dekhne ke liye kisi bhi developer par click karein.