gameLive product

İstanbul Chess

Live real-time multiplayer chess on Cloudflare Workers: one Durable Object per game for state isolation, WebSocket fan-out, server-authoritative clocks, and storage-backed reconnect. Ottoman vs Byzantine, playable now.

Sole engineer

Open live product

in production: Live
Durable Object per game: 1:1
authoritative clocks: Server
origin servers to run: 0

Live · playable now

Play İstanbul Chess at istanbulchess.com

Pick a house — Ottoman or Byzantine — and play a real opponent. Accounts, lobby and leaderboard are live; the board below is the architecture behind it.

Architecture

İstanbul Chess

Client
- Board UI - TypeScript
- WebSocket Session
- Auth + Profile
play + lobby
Edge Worker
- Routing + Auth
- Lobby - Matchmaking
- Leaderboard - Ratings
per-game isolation
Per-Game State
- Game Durable Object
- Server-authoritative Clocks
- DO Storage - Reconnect

Arrows show connections; hover a node to trace its links

Engineering details

One Durable Object per game: board, clocks and player seats are isolated by construction, so no game can read or corrupt another's state
Server-authoritative clocks — time is decided at the edge, not in the browser, so a client cannot manipulate its own remaining time
WebSocket fan-out from the game object pushes each move to both players without polling
Storage-backed reconnect: a dropped player rejoins mid-game and the position, clocks and history are restored
Lobby and matchmaking assign seats and open challenges before handing play to the game object
Accounts, ratings and per-house leaderboards on the same Workers stack
Runs entirely on Cloudflare's edge — no origin server to operate, patch or pay for while idle
Themed as Ottoman versus Byzantine: the interface commits to the setting rather than shipping a generic board

The challenge

Real-time multiplayer is where hobby projects usually stop: two players need the same board, the same clock and the same result, even when one of them loses their connection mid-game.

What I built

Shipped, deployed and still operating: every game is its own Durable Object, so state never leaks between boards; the server owns the clocks, so neither client can cheat them; and reconnecting mid-game restores the position from storage. Playable right now at istanbulchess.com — accounts, lobby and leaderboard included, built by a competitive player (second place in Istanbul, first at university and high-school level).

Have something in mind?

I'm open to backend and platform roles, contract or permanent. Based in the EU, available on-site in Belgium and the Netherlands or remotely worldwide.

Download CV

Architecture

Client

Edge Worker

Per-Game State

The challenge

What I built

Have something in mind?

Architecture

Client

Edge Worker

Per-Game State