FAQ

Does a candidate need to know the exact replication factor for Kafka to pass?
Yes. The judgment is clear: interviewers at Stripe, Uber, and Amazon mark any answer without a concrete replication factor as a 0 in the reliability rubric, leading to a No Hire.

Can I mention only high‑level design and skip the SLA numbers?
No. The debriefs at Google, Microsoft, and Amazon consistently penalize missing SLA specifics. The candidate who omitted SLA details in a Google loop received a 1‑score for “Latency Understanding” and was rejected.

Is it acceptable to propose a fallback to batch after the stream exceeds latency?
Never. The Uber HC ruled that a fallback must be an explicit, pre‑defined switch‑over, not a vague “we’ll fall back later”. Candidates who treated fallback as an afterthought received a 2 in “Trade‑off Clarity” and were not hired.

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