Rack Middleware Skill Tier 1: Quick Reference - Middleware Basics Middleware Structure Common Middleware Middleware Ordering Request/Response Access --- Tier 2: Detailed Instructions - Advanced Middleware Custom Middleware Development Request Logging Middleware: Authentication Middleware: Caching Middleware: Request Transformation Middleware: Middleware Ordering Patterns Security-First Stack: API-Focused Stack: Conditional Middleware Environment-Based: Path-Based: Error Handling Middleware --- Tier 3: Resources & Examples Complete Middleware Examples Performance Monitoring: Request ID Trackin…