1. HTTP/1.1, HTTP/2 & HTTP/3 advanced

    You migrate a mobile API to HTTP/2 and p99 latency gets worse for users on cellular networks, while p50 improves. Explain and decide what to do.

    1 min answer http2http3quichead-of-line
  2. Human in the Loop advanced

    A pipeline combines automated processing with human review at scale. How should the boundary between them be designed?

    2 min answer scale-aihuman-in-looproutingquality
  3. Human in the Loop intermediate

    A platform uses AI to propose substitutions when items are unavailable. Where should the human sit in the loop, and what determines it?

    2 min answer human-in-the-loopautonomyconfidenceescalation
  4. Human in the Loop advanced Multiple choice

    An AI system routes decisions to human review. The override rate is 0.3%. Is the oversight working?

    2 min answer oversightautomation-biasdesign
  5. Human in the Loop advanced

    Design the moderation path for user-generated content at high volume, where both false positives and false negatives are costly.

    2 min answer moderationmloversightdesign
  6. Human-in-the-Loop Design beginner Multiple choice

    A claims system shows the reviewer a risk score of 0.87, the recommendation Reject, and a confirm button with the recommendation already selected. Median time on screen is 4 seconds. Audit records this as human oversight. What is the smallest change that makes the oversight real?

    2 min answer human-in-the-loopautomation-biasoversightui-as-control
  7. Human-in-the-Loop Design advanced

    A fraud system routes flagged transactions to human reviewers, who approve or reject within a target of 4 minutes each. A campaign triples flagged volume overnight. Reviewer headcount is unchanged. What happens to the quality of the human oversight, and what should the design do about it?

    2 min answer human-in-the-loopautomation-biascapacityqueueing
  8. Human-in-the-Loop Design advanced

    A high-consequence decision requires human oversight of an automated recommendation. What makes that oversight meaningful rather than nominal?

    2 min answer human-oversightautomation-biasworkflowaccountability
  9. Human-in-the-Loop Design advanced Multiple choice

    An anti-fraud system routes flagged transactions to human reviewers. Audit shows reviewers approved 98% of cases with a median handling time of 3 seconds. The control is documented as human oversight. What is the most accurate finding?

    3 min answer human oversightautomation biasthroughputcontrols
  10. Human-in-the-Loop Design advanced

    An approval step has a 99.8% approval rate. What does that tell you and what would you change?

    2 min answer human-in-the-looprubber-stampingescalationautomation-bias
  11. Hydration Cost advanced

    A marketplace's pages paint quickly and feel unresponsive for several seconds after appearing. What is happening and how do you fix it?

    1 min answer hydrationinteractivityjavascriptperformance
  12. Hydration Cost advanced

    A page renders quickly and is unresponsive to input for several seconds on a low-end device. What is happening?

    2 min answer meeshohydrationinteractivityjavascript