Disney·Software Engineer·Onsite - System Design / Architecture
- Design an end-to-end clickstream ingestion and aggregation pipeline that handles roughly a billion events per day, covering everything from the client SDK through to the serving layer where analysts query daily aggregates.
- A user's device goes offline and syncs telemetry hours or even a day later. How do you make sure the daily aggregate stays accurate? Walk through how you'd handle late-arriving events, including what happens after the aggregate has already been finalized.
- Network retries cause duplicate events to show up in the pipeline. What's your strategy for exactly-once processing? Compare idempotent sink writes versus transactional two-phase-commit sinks, and explain where dedup state lives and how you keep it from growing forever.
- Traffic spikes 10x during a live event. How do you detect that the pipeline is falling behind, and what's your autoscaling and back-pressure strategy to catch up without dropping data?
- A bug in the aggregation logic shipped yesterday. How do you recompute corrected aggregates from the raw event store without disrupting live ingestion?
“This is the kind of question where you can talk for 45 minutes and still feel like you missed something.”