I want to build a full-stack, real-time chat application where users can register with email and password, create or join shared lobbies, and exchange messages instantly. The flow is straightforward: • Users sign up or log in (email + password auth only). • Any logged-in user can open a lobby that auto-generates a join link or QR code. • Friends scan or click to enter the same room, and everyone sees messages appear live. • Inside the lobby, participants can edit or delete their own messages, react with emojis, or drop quick voice notes, all without refreshing the page. Tech stack is fixed: FastAPI (Python) for all auth, REST endpoints, WebSocket handling, and business logic; React with plain JavaScript on the front end for a snappy, modern UI. I already have hosting ready, so container-ready code (Docker or simple deployment scripts) and an up-to-date README are part of the hand-off. Deliverables 1. Clean, commented FastAPI backend with JWT-based email/password auth, REST + WebSocket routes, and unit tests. 2. Responsive React interface that consumes the above, shows lobby lists, QR/invite sharing, live chat with emoji picker and voice-note capture. 3. End-to-end instructions so I can spin everything up locally and push to production in a single command. If you’ve built chat or real-time apps before with FastAPI, Socket.IO, or similar stacks, this should feel familiar. Let’s ship something dependable, easy to extend, and pleasant to use.