How I Built a Real-Time Multiplayer Chess Game with Video Calling Using Next.js, Socket.IO & WebRTC

I wanted to play chess with my friends online — but not just chess. I wanted to see their face when I take their queen. So I built NextBuild Chess — a free, real-time multiplayer chess game with built-in video calling. No sign-up, no downloads. Just share a link and play. Here's how I built it, and what I learned along the way. The Tech Stack Next.js 14 — App Router, but with a custom server (more on that below) Socket.IO — Real-time move relay and player coordination WebRTC — Peer-to-peer video