An edge caching playbook

Authenticated dashboards feel hostile to caching because personalization is everywhere. The trick is to separate stable shell data from volatile user-specific payloads.

We cache layout, navigation, and coarse aggregates at the edge while keeping sensitive mutations on origin with short TTLs and surrogate key purges.

Measure everything: stale-while-revalidate is powerful, but only when observability tells you what users actually experienced—not what the cache header claims.