Why Kingside ships chess features in hours when bigger sites take months
Hey,
About me, briefly: software engineer for ~20 years, chess is my hobby (online + OTB). The rest is more interesting.
The twist: Kingside is built primarily through AI (Claude). I drive architecture, product decisions, and the chess-domain side; the AI writes the code. The team is tiny — but with domain knowledge plus AI as the build muscle, iteration speed is honestly absurd. A feature request on the feedback board can go from idea to production in hours. Not days, not sprints — hours.
Some recent examples:
- Precision Training (a new mode where you defend winning positions against Stockfish) — designed and shipped end-to-end in one workday
- Drill exercises (board-vision tasks like "find all checks", "count attackers on e5") — built and live in a single session
- User-created courses with interactive quizzes and annotated diagrams — shipped in 2 days
And here's the fun part: you can shape what gets built next. There's a Feedback section right on the site — drop your idea, and there's a real chance it'll be live by the time you check back. No roadmap committees, no "we'll consider it for Q3." If it makes sense, it ships.
What you can actually do on the platform:
- Play — bullet to classical with custom time controls, separate Glicko rating per format. Plus play vs Stockfish at any strength (levels 1–20)
- Analyze your games — paste a PGN, Stockfish 18 runs right in your browser. Best line and multi-PV, every move tagged (
?!/?/??), Win-Draw-Loss bar on the critical ones. Save and share an analysis link - Import your games — pull from your Lichess or chess.com username directly, or upload a PGN file. Personal Workshop with all your games in one place
- Precision Training — engine-defense puzzles: a position right after a blunder, you take the winning side and have to hold the advantage against Stockfish for several moves. Full post-game review afterwards
- Train tactics — dozens of themes (forks, pins, mates, endgames, sacrifices, defensive moves...), filter by what you want. Daily puzzle. The platform also keeps a quiet mistakes diary of themes you fail most often, with a dedicated practice page for them
- Generate puzzles from your own games — paste a PGN, the engine finds your blunders and turns them into puzzles you can replay
- Drill exercises — board-vision training, not tactics. Count attackers on a square, find all checks, find pins, find forks, find loose or hanging pieces, find undefended attacks. Drill Sprint mode with leaderboards
- Puzzle Rush — 3-minute and 5-minute modes, leaderboards for both
- Master games archive — browse and search a database of master games by player, event, opening, or position (paste a FEN to find every game that reached it). Move-tree explorer from any position
- Build your own courses — write chess lessons with text and diagrams (arrows, highlighted squares), interactive quizzes, position trainers, opening drills, and endgame drills against Stockfish. Publish for everyone or keep private. Built-in spaced repetition for reviews
- Tournaments — Arena, Swiss, Round Robin. Public or invite-only, custom time controls and scoring
- Watch live broadcasts — major OTB events via the Lichess Broadcasts API, plus a separate relay for tournaments that aren't on Lichess
- Watch live games — see what other players on the platform are playing right now
- Bridge your own engine — if your machine struggles with browser Stockfish, run it locally and connect via WebSocket. Browser UI, your hardware
- Plus the basics: friends, direct messages, challenge friends, customizable boards, English + Russian interface, log in with Google or Telegram
Everything is free, no paywall.
Credit where it's due: the tactics puzzle database is the open Lichess puzzle dataset, and live tournament broadcasts pull from Lichess's public broadcast API (with a separate relay covering events that aren't on Lichess). Both data sources are open by design — we built the UI and integration on top, but the underlying data is theirs.
A small reality check, since this is going on a popular sub: despite a lot of work on optimization, we can't promise zero bugs at this stage — there will be rough edges. The site runs on AWS, but the team budget is tight, so the servers aren't the beefiest either. If you hit bugs or performance issues, please drop a note on the feedback board — we fix in order of impact.
I'm not claiming Kingside is better than chess.com or lichess overall — they've had years and large teams. The point is different: a small experienced team using AI well can ship serious chess features at a pace traditional dev cycles can't match. That's the experiment.
Site: kingside.site
Try it out, leave a feature request, and see how fast it gets built. What would you want to see added?