LANtern

Problem

Needed a local-network multiplayer trivia game that could run entirely within a LAN — no cloud dependency, no latency from remote servers. Players should be able to join from any device on the same network and compete in real time.

What I Built

A full-stack trivia game with a Bun + Elysia backend handling WebSocket connections via Socket.IO, and a React frontend for the player interface. The server manages game rooms, question rounds, scoring, and real-time state synchronization across all connected clients.

The application supports dual database backends — SQLite for local/development use and PostgreSQL for production — allowing flexible deployment without code changes.

Stack

• Runtime: Bun
• Backend framework: Elysia
• Frontend: React with TypeScript
• Real-time: Socket.IO (WebSockets)
• Databases: SQLite (local), PostgreSQL (production)

What I Learned

• Managing real-time state across multiple WebSocket clients requires careful synchronization to prevent race conditions during scoring.
• Bun’s native SQLite driver is significantly faster than Node.js equivalents for local game state persistence.
• Supporting dual databases forced a clean abstraction layer that made the codebase more portable.

Outcome

A working multiplayer game that runs over any local network. Players join via a room code, answer timed questions, and see live leaderboard updates.