Why Push-Based Systems Fail at Scale — and How Hybrid Fan-Out Fixes It
Real-time systems look simple on architecture diagrams. A user posts content, the backend publishes an event, and connected users instantly receive notifications through persistent WebSocket connections. At small scale, the model works beautifully. At large scale, it becomes one of the fastest ways to melt distributed infrastructure. Most push-based architectures fail for one reason: they assume traffic is evenly distributed. Production traffic never is. One user may have 50 followers. Another m

