just wrapped the cloudflare frontend loop last month. sharing notes because i couldn't find anything recent when i was prepping.
the process was: recruiter screen -> take-home -> 2 technical rounds -> behavioral/values round. total elapsed time was about 3.5 weeks, which is faster than i expected.
take-home. they gave me a prompt involving building a small interactive UI component using vanilla JS or a framework of my choice. no create-react-app boilerplate allowed, which is an interesting constraint. i used React but had to set up my own bundler. they're definitely looking at your setup choices, not just whether the thing works.
technical round 1: javascript deep dive. this surprised me the most. the interviewer went hard on JS fundamentals: closures, event loop, microtask queue order, this binding in different contexts. one question was about why a specific promise chain resolved in a particular order. felt like they want to know if you actually understand the runtime, not just React APIs.
technical round 2: system design lite. for an L4-ish role they didn't ask a full distributed systems design, but they did ask me to design a client-side caching layer for a high-traffic dashboard. discussion covered cache invalidation strategy, stale-while-revalidate patterns, and how i'd handle optimistic updates. very relevant to what they actually build (workers, edge caching).
behavioral round. cloudflare's values (especially 'customer obsession' and 'ship it') came up explicitly. came prepared with STAR stories and they asked mostly competency questions: conflict resolution, a time you pushed back on a spec, how you handled an incident. pretty standard, but you do need to have stories ready.
one thing: they asked about web performance metrics (LCP, CLS, INP) in real terms, not just definitions. i'd say know your core web vitals cold and be ready to talk about real-world trade-offs.
overall vibe was collaborative. interviewers were direct but not gotcha-y. team seemed genuinely excited about what they're building. i didn't get to the offer stage (got dinged on the system design round), but the process itself was well-run.