Rivvo

Rivvo is a messaging platform built to see how much of a real chat product one person can carry end to end: registration and OTP verification, direct and group conversations, status posts, voice and video calls, contact graphs, reports and an admin moderation console.

The backend is Express over MySQL with Socket.IO for presence, typing and call signalling; the frontend is React 18 and Vite. In production the backend serves the built frontend, so the whole thing deploys as one process.

Seventeen route groups and sixteen controllers on the backend, twenty-one pages on the frontend. The interesting parts are not the message list — they are key distribution, moderation and the call layer.

A chat app is the classic example of a project that looks small and is not. Sending a message is an afternoon. Everything around it — delivery state, read receipts, edits, view-once, blocking, group membership changes, key rotation when someone leaves, reporting, and an admin who can act on a report — is the actual system.

Group encryption metadata is where most hobby chat projects quietly give up. If a member leaves a group and the keys do not rotate, they can still read what follows. If keys rotate but are not redistributed, everyone else loses the conversation.

Moderation is the other half. A platform that accepts user-generated content without a report queue, a moderator role and an audit trail is not a product; it is a liability with a login page.