Backend Development Patterns Backend architecture patterns and best practices for scalable server-side applications. API Design Patterns RESTful API Structure Repository Pattern Service Layer Pattern Middleware Pattern Database Patterns Query Optimization N+1 Query Prevention Transaction Pattern Caching Strategies Redis Caching Layer Cache-Aside Pattern Error Handling Patterns Centralized Error Handler Retry with Exponential Backoff Authentication & Authorization JWT Token Validation Role-Based Access Control Rate Limiting Simple In-Memory Rate Limiter Background Jobs & Queues Simple Queue Pa…