← All case studies

Payment platform modernization for fintech

Confidential fintech client

fintech cloudbackenddevops

Challenge

The client operated on a monolithic Java architecture that couldn’t keep up with growing transaction volumes. Deployments took hours and required maintenance windows. Lack of autoscaling caused issues during peak hours.

Solution

We conducted a step-by-step migration - no big-bang rewrite. Key elements:

  • Monolith decomposition into microservices (domain-driven bounded contexts)
  • Migration to Kubernetes (EKS) with Terraform IaC
  • CI/CD pipeline with automated tests and canary deployments
  • Event-driven architecture with Apache Kafka for transaction processing

Results

  • 40% reduction in infrastructure costs (right-sizing + spot instances)
  • 99.99% uptime vs. 99.5% before migration
  • 8-minute deployments (vs. 4 hours previously)
  • 3x throughput increase with no hardware changes
"The PST team delivered a solution that cut our infrastructure costs by 40% and reduced deployment time from hours to minutes."

Jan Kowalski

CTO, fintech client

Published: 15 January 2026