Cloud Migration & Cost Optimization for a FinTech Platform

The Situation

Three years of rapid growth had left the platform’s cloud infrastructure in a state that its current team couldn’t fully explain. The original AWS environment had been stood up by a contractor who was long gone. The team had added to it incrementally, each addition making sense in isolation, none of them designed to work together efficiently.

The result: $420,000 in annual cloud spend with a 25% quarterly growth rate, deployment processes that required coordinating three engineers for four hours, and an on-call rotation that everyone dreaded.

The Diagnosis

Our assessment found several compounding issues:

Over-provisioning: Production databases and application servers sized for peak load that occurred 2% of the time, at full cost 100% of the time.

Architectural inefficiency: Synchronous processing patterns that should have been async, creating scaling bottlenecks and unnecessary redundancy.

Deployment risk: Manual deployment processes with no rollback capability — leading to the four-hour war-room approach to minimize human error.

No IaC: Every environment was manually configured. Inconsistencies between environments were a constant source of bugs and deployment failures.

The Decision

We recommended a phased approach:

1. Quick wins: right-size obvious over-provisioning, eliminate unused resources (months 1–2)
2. IaC foundation: adopt Terraform for all infrastructure (months 1–3, parallel)
3. Container migration: move from EC2-based workloads to EKS (months 2–4)
4. CI/CD implementation: ArgoCD-based GitOps deployment pipeline (months 3–4)

We presented cost models, migration risk assessments, and rollback plans for each phase before beginning.

The Build

Infrastructure as Code: We captured all existing infrastructure in Terraform before making any changes. This gave us an accurate baseline and a safe path forward.

Right-sizing: Comprehensive analysis of actual resource utilisation across all services. We reduced over-provisioned database instances, moved to auto-scaling for application servers, and eliminated seventeen unused resources that were generating charges.

EKS Migration: Phased migration from EC2-based deployments to Kubernetes, service by service, with parallel running during cutover.

CI/CD Pipeline: GitHub Actions for build and test; ArgoCD for GitOps deployment. Every deployment now runs in 22 minutes with automated rollback on health check failure.

The Result

• Cloud costs: $260K/year (was $420K) — 38% reduction, saving $160K annually
• Deployment time: 22 minutes (was 4 hours) — 90% reduction
• Deployment frequency: Daily (was weekly)
• Production incidents in 90 days post-migration: Zero
• Uptime: 99.97% (SLA is 99.9%)

What Holds

Twelve months later, the platform is still running on the architecture we designed. The team maintains and extends it independently. The Terraform repository has been updated 140 times by their own engineers. We no longer work with them on managed services — which is exactly what a successful engagement looks like.