Request flow diagram showing a React frontend querying a NestJS API with intelligent cache-checking logic. The API evaluates cache hit status and routes requests to Redis for cached data or PostgreSQL for database queries. This pattern reduces database load and latency by serving frequently accessed data from in-memory cache. Fork this diagram on Diagrams.so to customize for your tech stack, add error handling paths, or document cache invalidation strategies. The architecture demonstrates a common optimization technique for production applications handling high request volumes.