Node.js Caching in Production: Redis, In-Memory, and CDN Edge

Node.js Caching in Production: Redis, In-Memory, and CDN Edge Caching is the single most high-leverage performance optimization in most production Node.js systems. Done right, it reduces database load by 80%, cuts p99 latency from seconds to milliseconds, and gives your service headroom to absorb traffic spikes without scaling. Done wrong, it silently serves stale data, creates thundering herds, and introduces cache invalidation bugs that are harder to debug than the original latency problem. This guide covers the three caching layers that matter in production Node.js: Redis distributed caching, in-memory LRU caching, and CDN edge caching — with real patterns, real code, and the tradeoffs you need to know before you deploy. Layer 1: Redis Distributed Caching Redis is the standard distributed cache for Node.js production systems. It lives outside your process, survives deploys, and is shared across all your instances. Use it for any data that's expensive to compute or fetch, shared acro