I built a chess site where you don't need an account to play your friend.

Create a game → send one link → play.
No signup, no lobby, no ratings, no ads.

Busy? Correspondence mode: 1, 3 or 7 days per move.

Built solo in C#/.NET.
chessdox.com

The link previews on my chess site are PNGs my own code draws:

- an SVG path parser (M L H V Q C Z)
- a scanline rasterizer: 4 sub-scanlines, non-zero winding
- a TrueType reader, composite glyphs included (for accents)
- PNG chunks + CRC32

Only DEFLATE comes from .NET.

That card is a real one, drawn for a finished game on chessdox.com. Invites get the same treatment: "A friend challenges you to a game of chess", and no account is needed to accept.

I wrote a GIF encoder for chess replays in C#. No library.

Trick: after frame 1, each frame stores only the rectangle that changed.

A real 20-move game: 41 frames, 480×480, 235 KB. Median frame: 4.9 KB vs 16.6 KB for the full first one.

LZW written by hand.

Every finished game on chessdox.com can be exported as this GIF, PGN or a share card. Example game: chessdox.com/games/expert-r…

Chessdox is on Show HN today. Private chess with a friend from a link, written in C#. Feedback (and roasting) welcome: news.ycombinator.com/item?id=502600…

A live chess game on my server costs about 5 KB of RAM.

After 40 half-moves: 5,097 B. After 150: 5,092 B. Flat.

The trick: no move history in memory. Only the last 151 position keys; the 75-move rule means repetition can't reach further back.

The rest lives in SQLite.

That server runs chessdox.com: private games from one link, no accounts. C#, .NET 10.

My chess engine played Stockfish 18 for 92 games.

It lost all 92.

Then it played Leela Chess Zero 128 times and won 27.

Written from scratch in C#. One thread, 16 MB hash, 1s + 10ms per game.

What I learned 🧵

The Stockfish match was stopped by SPRT at LLR −2.95. With zero points you can't even compute a finite Elo.

Against Lc0: −137 Elo, 95% interval [−191, −88].

Every opening was played twice with colours swapped, and the binaries are pinned by SHA-256.

It's the computer opponent on chessdox.com: 4 levels, and Expert searches to depth 9 / 5M nodes / 3 s. Stockfish went 92–0 (1s+10ms bullet). Your turn.

Chess sites want an account before you can play your friend.

Mine wants a link.

chessdox.com

Play chess with a friend in 15 seconds.

No account. No app. Just a link.

♟️ chessdox.com

Honest part: my own engine lost all 92 games against Stockfish 18. 😅 Next post: what I learned building it.

Trump’s Russian Diesel Deal Tests Sanctions and Energy Policy ruspiracy.com/trump-russian-…

Deep Dive - Caching in .NET is finally here 🥳

After a full year of hard work, my 2nd course is out on @dometrain (30% off with "AUGUST30").

It's the conclusion to the journey we started with the 1st course, Getting Started.

I condensed 20+ years...

dometrain.com/course/deep-di…

Hi @thsottiaux there was a service outage. I think it would be fair to do a reset? What do you think? So nice for the weekend 😀

Markdown preview is officially on brew🎉

The butt-plug design is bad, but the fountain count is even worse. “More than 100” drinking fountains in a city as huge as London is embarrassing. Vienna has around 1,800 for about 2 million people. This should be a baseline, not a brag.