Download Your Edge Caching Guide

A CDN misconfiguration allowed a user’s personalized dashboard to be cached and served to thousands of other users. The cache hit ratio looked fantastic—94% of requests served from edge—until support tickets started arriving with users seeing each other’s private data. The problem: caching returned personalized content without realizing it couldn’t be shared.

Edge caching is a correctness problem first, performance problem second. Aggressive caching dramatically improves performance and reduces origin load, but incorrect configuration serves wrong content to users—sometimes catastrophically.

This complete guide teaches you how to design cache keys and responses that enable aggressive caching without correctness bugs.

Read this e-book to understand:

• Cache key design and Vary headers: preventing content cross-contamination without destroying hit ratios
• HTTP cacheability: what methods, status codes, and headers control whether responses cache
• Cache invalidation strategies: TTL, purge APIs, versioning, and stale-while-revalidate patterns
• Authentication and personalization: private vs. public caching with Set-Cookie and Authorization
• Query string handling and cache key expansion: performance vs. flexibility tradeoffs
• Conditional requests and origin shield: reducing origin load with If-None-Match validation
• Real-world case studies: caching bugs that served stale or cross-contaminated content, and how to prevent them

Download Your Edge Caching Guide now to cache aggressively while maintaining correctness and preventing content cross-contamination.