A browser-to-desktop multiplayer world inspired by Habbo Hotel: a cryptographically signed desktop client, a distributed real-time backend with a three-way trust model, and an AI pipeline that generates the art. Designed, built, and shipped by one person.
The client cannot simply be downloaded and run. It has to prove who you are, and that it has not been tampered with.
A one-time SSO token from the deep link is exchanged for a rotating 30-day refresh token (DPAPI-encrypted on disk) and a short-lived access JWT. Hitting Play trades that for a 60-second Ed25519 game JWT, handed to the Java client over stdin so it never shows up in a process listing. Four token types, each scoped to the narrowest lifetime its job allows.
The package streams from CloudFront as a resumable download with a running SHA-256 check, then is verified against an Ed25519-signed manifest: kid, signature, version, hash and size. These five invariants make downgrade and key-swap attacks fail closed. Only then does it extract (guarded against zip-slip and zip-bombs) and atomically install, keeping the last build for rollback.
Wails (Go + Svelte) · AWS S3 / CloudFront / KMS · Ed25519
Three callers, three trust mechanisms. The backend never treats them the same.
The web reads with a 24-hour session JWT; the game client reads directly with its 60-second game JWT, checked at the backend and again locally by the game server at join. Writes (trades, inventory, credits) come only from the game server, HMAC-signed with a 30-second replay window, so a patched client can't forge state. Live movement and chat run on a custom line-based TCP protocol; Kafka carries a fire-and-forget trade audit trail, Redis caches the profile page, and STOMP pushes room events to the browser.
Java · Spring Boot · MySQL · Kafka · Redis · STOMP
All the art that fills the world comes from the project's own pipeline. It is one of the three core systems, not an add-on.
A text prompt becomes catalog-ready furniture: image generation (FLUX / nano-banana), two-to-four chained isometric angles for view consistency, then a review step that sets tile size, category, collision, wall-or-floor placement and per-angle offsets before it goes live in-world.
Angular admin app · isometric tile mathA headless, LLM-drivable pixel-art editor with around 50 MCP tools for layers, frames, drawing and export. Its batch recolor generates every avatar combination (hair, eyes, top, trousers, shoes, skin) with perceptual matching that preserves shading and anti-aliasing. Open-source; I'm a contributor.
TypeScript · Model Context ProtocolRole, solo: product, art direction, full-stack, desktop client, cloud infrastructure, and the AI content pipeline.