A Safe CDN Cache Strategy for Content Sites

Classify every route

Separate immutable assets, public documents, frequently updated pages, personalized responses, APIs, admin pages, and health endpoints. Each class needs a different policy. ‘Cache everything’ is not a strategy.

Set explicit headers

Use browser and shared-cache directives intentionally. Immutable hashed assets can live for a long time. Public articles can use short browser freshness with longer shared freshness. Authentication, dashboards, and measurement endpoints should not be stored in shared caches.

Plan invalidation

Prefer versioned assets and predictable revalidation. Document how editorial changes, price changes, and emergency corrections reach visitors. Test purge behavior before relying on it.

• Route classes documented
• Private routes excluded
• Stale behavior chosen
• Purge path tested

Observe cache behavior

Record cache status, age, response time, and origin load. A high hit ratio is not automatically good if users receive incorrect content. Monitor correctness and origin protection together.