How to Build a Multiplayer Lobby in Unity with...

Building a multiplayer lobby is where most Unity real-time projects fall apart. Not the networking part — that's the easy bit. The hard part is everything around it: players joining and leaving mid-session, the host disconnecting and taking the room with them, a player's phone screen locking for 30 seconds and losing their slot forever. Most tutorials stop at "connected". This one doesn't. This is a complete walkthrough of building a production-ready lobby in Unity using socketio-unity — room cr