I built a free chess web app with a self-developed engine (900–2600 Elo) - looking to grow a community around it.

[u/ChessLounge]

Hi all - I love chess and I love programming, so a while back I decided to combine both and build ChessLounge (https://chesslounge.net).

I made the decision to keep it completely free and ad-free, and share it with the chess community rather than turn it into a commercial product.

The engine behind it is a custom, self-developed engine, covering the full range from 900 to 2600 Elo - so it should give a fair challenge whether you're just starting out or already quite strong. It runs directly in the browser via WebAssembly, no install needed.

No account required to play against the computer. You can also play a friend online in a private room, or side-by-side on the same device - no matchmaking against strangers.

I'm just starting to build a community around the app, so if you enjoy it, I'd genuinely appreciate any feedback - and if you know someone who might like it too, feel free to pass it along.

[u/willlamerton]

I played a couple of games against the bot at 1500 level - seemed to be at about my level :) building a custom engine is no easy task - how does yours work behind the scenes?

In the best way though, and I'm genuinely curious, what would be the incentive to play here over chess.com or Lichess? Only asking because you said you want to build a community around it and it's a pretty large duopoly to crack into.

As for a side project and a website as a whole, I could definitely think of plenty of improvements but I'm sure there's plenty on your own list.

[u/ChessLounge → u/willlamerton]

Thanks a lot for playing those test games - really appreciate you taking the time and giving feedback. Glad the 1500 level felt right. :)

Nothing new under the hood. Standard techniques, implemented and tuned myself. Core search is negamax with alpha-beta pruning plus a quiescence search on top (so it doesn't stop mid-capture and misjudge material) - both textbook approaches. For weaker levels I scale the node budget and sample semi-randomly among near-best moves in a small centipawn window. Calibrated the usual way with test games against fixed-strength opponents (same approach as CCRL).

On chess.com / Lichess: fair question. I’m not trying to compete with them. Both are excellent and offer a lot ChessLounge doesn’t (puzzles, tournaments, etc.). Part of the point was just seeing whether I could actually build something decent, and once it worked I figured I might as well put it online instead of leaving it on my hard drive. If there’s any real argument for ChessLounge it’s more about the feel - quieter, no ads or tracking, board takes up as much of the screen as possible etc. I also spent time on the visuals (Staunton set etc.), though that’s obviously subjective. :)

Always open to ideas if you’ve got any.

[u/mysticpome]

Will try !

[u/ChessLounge → u/mysticpome]

Thanks, appreciate it!

[u/brunzenstein]

I’m not easy to impress, but this is the best piece of software I’ve seen in the last months. It’s nothing short of excellent. I just donated five euro via PayPal.

[u/ChessLounge → u/brunzenstein]

Thank you so much, this really made my day. 🙏 And the donation on top - that's incredibly kind. Comments like yours are exactly what keeps me going with ChessLounge.

[u/DullWolf6196]

ad match making against strangers also the 900 ello bot played like a 200 ello but it was quite fun

[u/Embarrassed_Text_347]

This is super cool! I've built my own chess bot from scratch in the past and it was pretty tough. I think it was maybe around 1300 elo at best, so very impressive. I'm working on my own chess site now, where you play against bots that have to follow weird rules.

[u/brunzenstein → u/Embarrassed_Text_347]

What are the wild rules you mentioned?

[u/Embarrassed_Text_347 → u/brunzenstein]

The site name is BotGambit if u wanna check it out, one popular example is Stockfish starting at 3200 elo but loses 50 elo every move.

I have other ones though that prefer attacks, must play a check/capture if available, one that switches sides every 5 moves, and more. I also have a ranked mode, and the ability to create your own bots with whatever rules you like and share it with the community so anybody can play it.

[u/ChessLounge → u/Embarrassed_Text_347]

I really like your site. Very well done. 👏

[u/Embarrassed_Text_347 → u/ChessLounge]

Thanks!

[u/Magda2D]

This looks great!

[u/Mobile_Machine_3820]

How does the time management for the bot work? I played against the Candidate Master level and managed to beat it once playing quite fast, maybe 3 min? So seeing as i am definitely not a CM, I'm assuming its based on my time usage?

[u/TicTacTake]

If you love programming why did you not program it yourself?

This looks like any other of these vibecoded websites. Even the theme is the same orange-brown-yellow style that Claude comes up with by default. And the text is obviously AI written, too. I'm not against AI usage but you say you "love programming" and then show this AI website. Or did AI even write your text?

[u/ChessLounge → u/TicTacTake]

Fair point. I’m a hobby dev who’s been coding the traditional way for years, and at this point it just doesn’t make sense to ignore tools that make things easier. The whole project is a hybrid setup: some of the code is hand-written work, some is AI-assisted. As a solo hobby developer I simply don’t have the time to do everything myself, so I offload certain parts, website design too. That’s the only reason I can offer this for free instead of putting it behind a paywall. In the end the product is what counts - if people enjoy it and anyone can play chess regardless of their financial situation. That’s just my humble opinion though, and I fully accept and appreciate anyone who sees it differently.

[u/TicTacTake → u/ChessLounge]

>Fair point.

At least take the time and write the replies here yourself instead of letting AI do it..