This project is a simplified system design implementation of a real-time chat system inspired by Discord. It focuses on low-latency messaging, persistent chat history, and real-time presence across channels and servers.
Real-time communication platforms must deliver messages instantly while supporting large groups of users, multiple channels, and persistent message history. This project explores how to design a simplified version of a chat system that handles message delivery, user presence, and channel-based communication at scale.
- Understand real-time messaging system design
- Learn how WebSocket-style communication works conceptually
- Explore low-latency message delivery strategies
- Understand channel-based architecture and fanout models
- Learn how presence and user status systems work
- Explore tradeoffs between consistency and real-time performance
- Build intuition for scalable chat systems
- Send and receive messages in real time
- Channel-based communication
- Message persistence and retrieval
- Servers (guilds) containing multiple channels
- Channel-based message segregation
- Basic membership model
- Live message delivery to connected users
- Presence updates (online/offline/idle conceptually)
- Basic event broadcasting system
- Persistent chat logs
- Paginated message retrieval
- Ordered message streams
- Connects to server via real-time connection (WebSocket concept)
- Sends and receives messages
- Maintains local message state
- Handles real-time connections
- Routes messages to correct channels
- Broadcasts events to connected clients
- Stores messages per channel
- Stores user and server metadata
- Supports efficient history retrieval
- Low-latency message delivery at scale
- Handling large numbers of concurrent connections
- Message ordering guarantees
- Fanout strategy for group channels
- Presence consistency and update frequency
- Tradeoffs between memory usage and persistence
- Message Queue (event distribution backbone)
- Rate Limiter (spam and abuse prevention)
- Distributed Cache (hot channel/message optimization)
- Load Testing (connection scalability testing)
- Monitoring (latency and delivery metrics)
🟡 Planned