Lichess: Year in Review 2023

As another year passes, we want to share some highlights of our work, achievements and projects over 2023.

2023 has been a year of massive community growth for us. Much of what we have achieved this year simply would not have been possible without so many people who have kindly donated their time to us, and so many people who have generously donated money to support our projects and goals. From January 2024, we will continue our work in an online chess landscape that is marching towards a monopoly. This trend is not unique to chess -- consolidation is happening across the internet and wider world.

But Lichess remains strong in spite of these challenges. We're a charity that's run by the community, for the community. Every cent donated to us is reinvested directly back into chess more widely; none goes to investors, shareholders or private equity firms. It's your support that has helped us outlast competitors with countless millions of dollars in investment and equity-backing, and your belief in our mission and purpose that helps to inspire us every day. Support us today to help ensure free chess, for everyone, forever.

Growth in contributions

We've had 155 first-time code contributors this year, a massive number given that in over a decade we've had 812 code contributors in total. 35 different projects have received contributions, and nearly 400 of these code changes have been from first-time contributors! We set up our Gitpod workspace which streamlines the contribution process.

Code is more than making new features; it's also maintaining it, managing updates and conflicts, keeping it optimised, and fixing any bugs or glitches that appear. This part of code contribution is effectively what keeps Lichess running smoothly, and creates a stable foundation allowing cool new features or projects to be expanded on top of it. A massive thank you to everyone involved!

Want to help us? We're always looking for contributors, and not just in code. Check out our contribution guide for more info.

Mobile updates

Around a year ago, growth in user donations and support allowed us to employ a full time mobile app developer to create a new Lichess mobile app. A year on, @veloce and nearly 20 other contributors have made great progress. Many features are implemented, such as puzzle training, puzzle storm, puzzle streak, the puzzle dashboard, leaderboards, Lichess TV, and a lot of backend work was recently completed, that also now allows games to be played and basic analysis.

Thanks to everyone on Lichess Discord for helping with beta testing the app so far. We will soon ask more users to join the beta. If you want to help create the new mobile app, you can join the Lichess beta testers team. We plan to send out a team message sometime in the next few weeks.

Better performance

Scalachess, our website code that checks the legality of every player move, has been rewritten from scratch and is now 50x faster. Lichess developer Thanh used many advanced techniques to optimize nearly every aspect of our chess logic in a heroic six-month effort. The result is a substantial increase in simultaneous game hosting capacity!

Scalachess benchmark notably showing +4575% in antichess move generation speed

Over 5 billion rated games

In 2023, we crossed over 5 billion standard rated games played on Lichess and stored in the Lichess games database. Similarly, March 2023 gave us our record of standard rated games played on Lichess in a single month (108 million), with over 1 billion games played across 2023 alone. That's a huge number of games and traffic for a charity with only two full-time developers, and running on roughly €550,000 per year!

Massive Broadcast growth

Our PGN Broadcasts of over-the-board chess tournaments have received a lot of love this year. Dozens of new features have been added, such as showing clocks on the multiboard view, allowing 128 games to be shown in a single broadcast, and showing tournament schedules and leaderboards on some events. 7,709 OTB tournaments were hosted entirely for free on Lichess over 2023, with dozens of contributors and thousands of user-uploaded tournaments making it the biggest year for our PGN broadcasts.

Stonks

Meanwhile, we are planning further improvements to broadcasts given the massive amounts of feedback we've received over the year and especially the last few weeks.

Supporting and Partnering with OTB chess

In 2023, as well as hosting hundreds of hybrid and online events from other chess organizations, we've more formally partnered and worked with national federations, international federations, and major chess organizations. Over the summer, we collaborated with the Kazakhstan Chess Federation to provide online tournament support to the Kazakhstan Cup. Over 350,000 games of chess were played, with Lichess sending multiple titled players to the OTB events with expenses covered. We've also partnered with the newly formed Women in Chess Foundation, an effort to make the chess world safe and welcoming to women and girls. We were also Broadcasts Partner to the Asian Chess Federation, ensuring the PGN transmission of the tournament was relayed accurately to Lichess and other platforms.

If you're involved with a major chess organisation, feel free to get in touch to see how we can potentially collaborate!

Lichess online events

The Lichess Bundesliga celebrated its 400th edition on 24th December. Overall the league counts almost 2 million registrations since its beginning on March 2020. The House Discord server won the yearly season 2023, overall for the fourth time in a row.

Meanwhile, our regularly scheduled Titled Arena have continued strong, with direct Lichess prize funds amounting to around $25,000 this year, which is roughly about 5% of our annual revenue. Indirectly, Lichess has supported dozens of prize fund events, some providing further significant prize funds to the wider chess community.

The Lichess4545 league continues strong, entering season 38. Starting on January 15th, registration is now closed - but keep an eye out for season 39 if interested in organised longer play matches online!

Lichess crossed 100 languages

The incredible Crowdin translation team have fixed thousands of translations, UI issues in translated languages, and helped with greater support for right-to-left languages. Thanks to this incredible community effort from nearly 3,000 contributors, Lichess is now partially available in over 100 languages spoken in the world, with around 40 of these fully translated.

New features

User flairs

Registered users can now optionally select flairs to represent them. A small visual graphic appearing next to the username, it's an extra bit of personalisation and colour. User flairs can be selected and chosen in user settings --- which have also had a bit of a revamp to allow a direct URL to each user setting.

New web analysis engines

A suite of new engines, headlined by Stockfish 16, are now available for use in web analysis, study, and puzzles. These updates offer a +60 to +120 Elo improvement over the previous Stockfish 14 NNUE, and the new Fairy Stockfish NNUEs offer anywhere from +90 up to +1100 additional Elo for variants. Many thanks to the Stockfish team for their commitment to making this free software, open source chess engine available to the world.

Feed

Our homepage has received a bit of a revamp. Eagle-eyed users will have noticed that if you scroll down to the bottom of the homepage, a new feature, called feed, has made its home there. You can also check it out at lichess.org/feed. Feed gives a regular update of Lichess and chess world news, updated regularly.

Voice recognition

You can now play games and puzzles with voice commands while doing your favourite activities, like woodworking, shaving, or reeling in a big fish.

https://www.youtube.com/watch?v=YqvyfgiyMoU

Moderation statistics

In 2023, our team closed over 567,000 reports, including:

• 93,000 reports for cheating
• 298,000 reports for communication infractions
• 87,000 reports of sandbagging or boosting
• 89,000 miscellaneous reports

A huge number of these reports came directly from you. We have many automated systems in place, but user participation is necessary to keep Lichess fun for all. In 2023 alone, we:

• flagged 72,000 accounts for cheating using external assistance
• flagged 20,000 accounts for sandbagging or boosting
• sent 176,000 warning messages to users for various infractions
• removed chat permissions from 72,000 accounts
• communicated with users over 36,000 times through our appeals system

The vast majority of players are well-behaved and follow the rules, so thank you! Here's more about our reporting, fair play, and communications guidelines.

We also added a new report type. Sexism and sexual harassment has always been against our Terms of Service, but it is now a specific option when making a report.

Lichess meetup 2023

Continuing our annual tradition, the Lichess team met up and worked together in Barcelona in 2023. Hosting a community event on a lazy September afternoon, over a hundred people joined us to informally play blitz chess in the autumn sun. Read about it in our summary blog and keep an eye out for our 2024 plans!

Some of the Lichess team who were able to make it to Barcelona

Around the World

Our team was present at several events around the world this year. Our Director of Operations, Theo Wait (@Cynosure), represented Lichess on a number of occasions in Kazakhstan: at the World Championship match, and at the Asian Zonal. He was also kindly invited to Bhubaneswar in India by the state government, where he gave a talk on digitalizing chess in schools and education. While there, he was fortunate enough to see the incredible work of ChessBase India in teaching chess to all across India, visiting an orphanage in Mumbai where Sagar Shah volunteers time and donates equipment to the children. Additionally, FM Jens Hirneise (@Jeffforever), a significant contributor in several areas to Lichess, played with admirable results in the FIDE World Rapid Championship in Samarkand, as well as visiting multiple chess clubs around the world.

Theo playing against one of the orphans of the Chembur Children's Home in Mumbai

Finance and Governance

As a registered French charity, our independently audited accounts for 2022 were published in June (link to PDF). Our total income that year was around €579,000 -- 95% from user donations. This was 2% lower than our 2021 income. Our total expenses came to €419,000 -- 15% higher than 2021 -- meaning we had a surplus of just under €150,000. Although our 2023 accounts won't be finalised until next summer, the numbers should be reasonably similar to 2022. Our costs have increased in some areas such as moderation and administrative support, but we've achieved savings in other areas, for example by securing longer contracts for some of our servers.

In terms of governance, Lichess has been growing and becoming more complex with thousands of contributors, and according to SimilarWeb we briefly broke into the top 200 websites in the world in terms of traffic in 2023 (although our traffic is certainly underestimated by these services, given how SimilarWeb calculates it, and our approaches towards trackers, etc). Given this significant scale and complexity, much discussion and work has been going on internally with how we are structured, with various committees meeting regularly to track how the main areas of Lichess are faring, challenges they are facing, and what we need to do in the long-term, as well as learning from those who have gone before us, both in the open source project space, and in industry.

Further reading

As usual, these are just some highlights of our work over the year. More regular updates can be found directly from various sources, like our GitHub logs, our changelog, our social media, and on our Discord.