How to Build Scalable Real-Time Systems Using WebSockets and Redis Pub/Sub

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A technical deep-dive published on tamiz.pro outlines how developers can combine WebSockets and Redis Pub/Sub to build resilient, low-latency real-time systems. WebSockets enable persistent, full-duplex client-server communication over a single TCP connection, eliminating the overhead of repeated HTTP requests. Redis Pub/Sub complements this by providing a fast, in-memory message broadcasting layer where publishers and subscribers remain loosely coupled. The guide covers multiple architectural patterns, from single-server setups to multi-node WebSocket clusters backed by Redis Sentinel or Cluster for high availability. It also addresses practical concerns such as horizontal scaling, load balancing, backpressure handling, and message delivery guarantees.

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