Building Realtime Apps

Real-time capabilities are essential for modern collaboration tools. Here's how I architected a WebSocket server capable of handling 10k+ concurrent connections.

The Stack

• Node.js: Event-driven runtime.
• Socket.io: Robust WebSocket library with fallback support.
• Redis: Pub/Sub for scaling across multiple server instances.

Handling Connections

Managing connection state is tricky. We implemented a custom heartbeat mechanism to detect zombie connections and clean up resources efficiently.

io.on('connection', (socket) => {
  console.log('User connected:', socket.id);
  
  socket.on('join_room', (room) => {
    socket.join(room);
  });
});

(Full tutorial coming soon...)