E-commerce cloud migration
40% cost reduction
Monthly AWS spend dropped after rightsizing and autoscaling — without sacrificing peak-sale performance.
A retail brand outgrew fixed servers every festival season. We moved them to AWS with zero checkout downtime and gave finance predictable cloud bills.
- Client
- D2C retail · High-traffic storefront
- Duration
- 14 weeks
- Stack
- AWS · Kubernetes · Terraform · CloudFront
Diwali and long-weekend sales regularly saturated their VMs. Engineers scaled manually at 2 AM; finance absorbed over-provisioned servers the rest of the quarter. They needed elasticity, observability, and a migration path that did not gamble with checkout.
Outcomes at a glance
Rightsizing and scheduled scale-down on non-peak hours.
Phased cutover with continuous synthetic transactions through migration weekends.
Autoscaling handled record sale day without manual intervention.
Kubernetes rollouts with automatic rollback on failed health checks.
The challenge
Traffic spikes were predictable; capacity was not. Auto-scaling was effectively "page someone." CDN coverage was partial, so image-heavy catalog pages hurt mobile conversion in Tier-2 cities.
Deployments were monthly because rollback was scary. Merchandising wanted weekly campaign landings; infrastructure lag became a marketing bottleneck.
Cost visibility was a spreadsheet exercise. Tags were inconsistent, so finance could not attribute spend to storefront vs. admin vs. batch jobs.
Our approach
We mapped workloads to EKS with Horizontal Pod Autoscalers tuned on real sale curves, not generic CPU thresholds. Terraform managed environments so staging mirrored production topology.
CloudFront cached static assets and product images at the edge; origin shield reduced load on the catalog API during flash promotions.
We migrated in waves: read-only catalog first, then cart, then checkout — each with health-checked load balancer weights and rehearsed rollback.
How we delivered it
Weeks 1–2 · Assessment
Dependency map, RPO/RTO targets, tagging strategy, and cost baseline.
Weeks 3–7 · Platform build
EKS clusters, Terraform modules, CI deploy pipelines, observability stack.
Weeks 8–11 · Workload migration
Phased traffic shift with synthetic checkout monitors every minute.
Weeks 12–14 · FinOps
Rightsizing, savings plans, dashboards for engineering + finance.
Migration without betting the business
Synthetic monitors hit add-to-cart and payment callbacks every sixty seconds from three regions. If error rates climbed during a traffic shift, weights rolled back automatically — no heroics required.
Runbooks lived in the repo next to Terraform modules so on-call engineers had one source of truth.
- Blue/green services for checkout
- Database replication lag alarms before promoting traffic
- Game-day rehearsal before the first major sale post-migration
Cost governance that stuck
Mandatory cost tags, weekly FinOps reviews for the first two billing cycles, and anomaly detection on the payer account caught orphaned resources before they became line items nobody recognized.
"Last sale season we slept. Autoscaling did the boring work — and finance actually thanked us for the AWS bill."
Planning something similar?
Tell us about your constraints, timeline, and what success looks like. We will share an honest assessment — including whether we are the right fit.