caching-patterns

Caching for NestJS APIs on Fastify with Redis - when to cache, HTTP caching (Cache-Control, ETag), application caching with @nestjs/cache-manager, cache-aside versus read-through versus write-through, TTLs, key design, invalidation, stampede protection, negative caching, in-memory versus distributed, consistency, Redis memory and eviction, hit-rate observability, testing, plus a short performance triage. Load when adding or debugging a cache, setting HTTP cache headers, or when an endpoint is slow.