intermediate

Cloudflare

Edge platform services for DNS, CDN, WAF, Workers, static hosting, object storage, SQL, KV, and coordination primitives.

Cloudflare interviews test edge-first thinking: DNS proxying, CDN caching, WAF rules, Workers for request logic, Pages for static frontends, R2 for object storage, and D1/KV/Durable Objects for edge data patterns. FullStack JS teams often deploy Workers and Pages alongside a traditional origin API.

Subtopics: DNS, CDN, WAF, Workers, Pages, R2, D1, KV, Durable Objects.

On interviews: cache static assets at the edge, run auth or A/B logic in a Worker, explain cache key pitfalls, and when Durable Objects beat KV.

Common pitfalls: orange-clouding internal admin hosts; caching authenticated API responses; assuming Workers are full Node.js; ignoring eventual consistency in KV.

The trade-off is low-latency global distribution versus runtime limits and edge-appropriate data models.

Checklist:

Separate cacheable public assets from private API traffic.
Test purge and cache-key behavior before launch.
Match storage primitive to consistency needs.
Keep secrets out of client-side Worker bundles.