- name
- CDN
- slug
- cdn
- description
- Configure, optimize, and troubleshoot CDN deployments with caching strategies, security hardening, and multi-provider management.
When to Use
User wants to set up, optimize, or debug a CDN. Covers provider selection, caching, security, and performance monitoring.
Quick Reference
| Topic | File |
|---|---|
| Provider comparison & CLIs | providers.md |
| Security hardening | security.md |
| Caching strategies | caching.md |
| Troubleshooting | troubleshooting.md |
Core Capabilities
- Provider selection — Compare Cloudflare, CloudFront, Bunny, Fastly based on use case, traffic, budget
- Cache configuration — Set optimal cache-control headers, TTLs, cache keys
- Security setup — SSL/TLS, WAF rules, DDoS protection, origin shielding
- Performance monitoring — Cache hit ratios, TTFB, regional latency
- Invalidation — Purge strategies, CI/CD integration, tagged invalidation
- Cost optimization — Bandwidth analysis, tier recommendations, multi-CDN strategies
- Troubleshooting — Debug cache misses, stale content, origin overload
Cache-Control Checklist
Before deploying, verify:
- [ ] Hashed assets (JS/CSS) →
Cache-Control: public, max-age=31536000, immutable - [ ] HTML pages → Short TTL or
no-cachewith revalidation - [ ] Images → Long TTL with content-based URLs or versioning
- [ ] API responses → Usually
no-storeunless explicitly cacheable - [ ] User-specific content →
privateorno-store
Security Checklist
- [ ] TLS 1.2+ enforced, weak ciphers disabled
- [ ] HSTS enabled with appropriate max-age
- [ ] Origin IPs hidden, authenticated origin pulls configured
- [ ] Rate limiting on sensitive endpoints (login, API)
- [ ] Security headers: CSP, X-Frame-Options, X-Content-Type-Options
Common Mistakes
- Caching user-specific responses (auth tokens, personalized content)
- Using
max-agewithoutimmutablefor versioned assets - Purging entire cache instead of targeted paths
- Ignoring
Varyheaders (cache poisoning risk) - Origin not rejecting direct access (bypassing CDN protections)
Decision: Do I Need a CDN?
Ask about:
- Geographic distribution of users
- Current page load times and Core Web Vitals
- Static vs dynamic content ratio
- Traffic volume and patterns
If users are mostly local and traffic is low → CDN may add complexity without benefit. If global users OR heavy static assets OR need DDoS protection → CDN adds value.