Scalable backend architecture patterns for Node.js, Express, and Next.js applications.

• Covers RESTful API design, repository pattern for data abstraction, service layer separation, and middleware pipelines for request processing
• Includes database optimization techniques: query selection, N+1 prevention, transactions, and Redis caching strategies
• Provides authentication and authorization patterns: JWT validation, role-based access control, and rate limiting implementations
• Features error handling with centralized handlers, retry logic with exponential backoff, and structured logging for monitoring
• Demonstrates background job queues, cache-aside patterns, and practical code examples across all architectural layers