Real-time Chat App
WebSocket-based chat application with end-to-end encryption, user authentication, and message history.
Overview
The Real-time Chat App demonstrates modern web technologies for building interactive communication platforms. The application prioritizes security, performance, and user experience.
Core Features
Real-time Messaging
Instant message delivery using WebSocket connections with Socket.io ensures users receive messages with minimal latency.
End-to-End Encryption
Messages are encrypted on the client side using TweetNaCl.js before transmission, ensuring privacy even from server administrators.
User Authentication
Secure JWT-based authentication with refresh tokens provides a robust security model.
Message History
Persistent storage of messages in MongoDB allows users to retrieve conversation history across sessions and devices.
User Presence
Real-time presence indicators show which users are online and when they're typing.
Technical Implementation
Frontend
- React with TypeScript for type safety
- Socket.io client for real-time communication
- End-to-end encryption with TweetNaCl.js
- React Query for state management
Backend
- Node.js with Express server
- Socket.io for WebSocket management
- MongoDB for persistent storage
- JWT for authentication
Security
- HTTPS/WSS for encrypted transport
- JWT token rotation
- Input validation and sanitization
- Rate limiting on API endpoints
Performance Optimizations
- Connection pooling for database
- Message pagination for efficient history loading
- Lazy loading of user avatars
- Client-side message caching
Lessons Learned
- WebSocket connection management at scale requires careful attention to memory leaks
- End-to-end encryption adds significant complexity but is essential for privacy
- Real-time features benefit greatly from comprehensive error handling and fallback mechanisms
Project Impact
📈 10k+ active users