Systems · Week 6
Week 6: Live product spikes
Commentary feeds, schedulers, flash sales, impressions, and matching.
Week 6: Live product spikes
Commentary feeds, schedulers, flash sales, impressions, and matching.
Outcomes
- Explain the failure drill for each lesson in this week without notes.
- Complete linked labs where present and keep a short metric log.
- Tag each system with the pattern cards you actually used.
- Live commentary feed Fan-out of live events with catch-up and retention bounds.
- Task scheduler Due tasks, lease workers, and exactly-once *effects* via idempotency.
- Flash sale inventory Reservations that prevent oversell under extreme concurrency.
- Impressions counting High-rate counters with approximation and aggregation windows.
- Ride-hailing match Geo matching under churn: freshness, leases, and fairness under load.