Real-Time Collaboration Platform

Overview

A collaborative coding platform that enables multiple users to edit documents simultaneously with live presence detection and real-time synchronisation. Built with Socket.io for WebSocket communication, Redis for session management, and a microservices Node.js backend.

Challenges

Handling concurrent edits from multiple users without conflicts or data loss
Scaling WebSocket connections across a microservices architecture
Maintaining consistent state between clients when connections drop and reconnect

Solutions

Implemented operational transformation logic to reconcile concurrent edits and maintain document consistency
Used Redis pub/sub to broadcast events across microservice instances, enabling horizontal scaling of Socket.io
Built a reconnection protocol that replays missed events from a MongoDB-backed event log on client reconnect

Languages & Tools

TypeScript

React

Node.js

Socket.io

Redis

MongoDB

WebSockets

Winston