How We Would Survive Black Friday Without Adding 40 Engineers

02 — Our approach

We would containerise the storefront and checkout flows, but the real work would not be the containers — it would be understanding traffic patterns. We would spend the first 3 weeks tracing every user journey and expect to find that the majority of database load comes from a handful of N+1 query patterns in the product catalog. Fixing those queries would give more headroom than any infrastructure change. We would add a CDN with edge caching for static assets and product images, build autoscaling that reacts to queue depth (not just CPU), and set up a war room dashboard the business team can actually read — revenue per minute, not CPU percentage. The biggest negotiation would likely be with the merchandising team: they want to push price updates live every 15 minutes, which busts the cache. We would work toward a batch window during peak hours.