Question bank

4,310 interview questions, answered.

Reference answers, what the interviewer is really testing, how it is graded, and the follow-ups that come next.

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4,310 questions

  1. 4273Edit a guide that says retries guarantee one email and tells users to try again after any error. Supplied facts are at-least-once delivery, possible consumer restart, and a provider with an operation-key contract.MediumBehavioralTechnical
  2. 4274A pilot customer asks for a live dashboard, but the observed task is a weekly spreadsheet built from three exports. Define the next useful test.MediumProductSystem design
  3. 4275Two engineers serve ten pilots at five exports per minute. A proposal adds six microservices. What evidence would justify that cost?MediumSystem designTechnical
  4. 4276A report uses five calls at 0.02 units each and 0.03 compute units. Ten percent need two additional calls. Estimate average direct cost and one containment rule.MediumSystem designTechnical
  5. 4277A new version removes a field required by the previous application. The release fails. Why is code rollback alone insufficient?MediumSystem designTechnical
  6. 4278Thirty users are invited, eighteen start setup, twelve export successfully, and seven activated users return at the next relevant interval. All twelve activated users had a full follow-up window. Report the useful rates with limits.MediumDataSystem design
  7. 4279The worker process is healthy while oldest pending age rises. What should the only available engineer inspect and communicate?MediumBehavioralSystem design
  8. 4280Four engineer-days must cover an active access defect with a one-day containment-and-verification estimate, a failing paid-user workflow with a one-day diagnosis-and-fix estimate that remains uncertain, and a five-day prospect integration. Propose a feasible sequence and explain the opportunity cost.MediumProductSystem design
  9. 4281A save submits title Maple at version 7. Before it returns, the user types Birch and navigates to another record. Specify where the response may update state.MediumCodingTechnical
  10. 4282Two task creations overlap. The second succeeds, then the first fails validation. Why can restoring the original list corrupt the interface?MediumCodingTechnical
  11. 4283A server-rendered page serializes a full customer record into a client component and uses a project-only shared cache key. Identify two independent risks.MediumDataCoding
  12. 4284A job UI sees version 6, then version 4, then loses its event stream. Design recovery without restarting the job.MediumSystem designCoding
  13. 4285Design a deterministic test for an export whose acceptance response disappears after commit.MediumCodingTechnical
  14. 4286A page waits 80 ms for session, then serial independent calls of 220 and 350 ms, then renders for 70 ms. Estimate the benefit of parallel calls and state when it is invalid.MediumDataCoding
  15. 4287A model predicts at 09:00. A feature event occurred at 08:58 but arrived at 09:03. A backfill later rewrites its timestamp. How should the historical training row be built?MediumDataAI ML
  16. 4288You have five visits per patient and want to predict outcomes for new patients at future hospitals. What validation design and limits would you state?HardDataAI ML
  17. 4289Only transactions selected for review receive confirmed fraud labels. The team wants to label all unreviewed transactions clean. Explain the problem and a first audit.HardDataAI ML
  18. 4290A model's live scores change with the composition of each request batch. The estimator weights are identical to training. What transformation bug would you test?MediumAI MLTechnical
  19. 4291At one threshold TP=45, FP=55, FN=15, TN=885. False negatives cost 80 and false positives cost 3. Calculate precision, recall, and cost; state what else you need before deployment.MediumDataAI ML
  20. 4292A classifier has scores in [0, 1] and preserves its ranking after every score is squared. What can change in expected-cost decisions and how would you evaluate it?MediumDataAI ML
  21. 4293Precision falls after a new region launches, while latency and feature missingness remain stable. Mature labels show the old region unchanged. What is the next diagnosis?HardAI MLTechnical
  22. 4294Offline ranking improves, live clicks rise, and completed user tasks fall. How would you decide whether the candidate is useful?HardDataAI ML
  23. 4295A colleague can reload weights but cannot reproduce the reported score. What experiment identity and first checks do you require?MediumAI MLTechnical
  24. 4296A momentum run resumes with correct weights but zero velocity. With w=2, v=3, next gradient=1, momentum=.9 and learning rate=.1, compare correct and weights-only next parameters. Use v_next = 0.9*v + g and w_next = w - 0.1*v_next, with no Nesterov, dampening, or weight decay.MediumDataAI ML