Case study · Fintech

Scaling a global payments platform without downtime.

A fast-growing payments provider partnered with Velinsa to re-architect a monolithic system into an event-driven platform that could support new markets and higher volumes without sacrificing compliance or reliability.

Region: Multi-region, serving EU and APAC Duration: 10 months Squad: 8 engineers, 1 architect, 1 PM
Client context

From monolith constraints to growth blocker

The client’s core payments engine was a single monolithic application deployed to a small number of regions. Each new feature increased complexity and slowed down releases, and the team struggled to support new products and regulatory changes.

  • Release cycles of 6–8 weeks with coordinated “all-hands” deployments.
  • Growing backlog of partner integrations and region-specific requirements.
  • Limited visibility into transaction flows and failure modes.
Velinsa scope

Designing a resilient payments platform

  • Define target architecture and migration strategy.
  • Implement event-driven services around a central payments ledger.
  • Introduce observability and incident management practices.
  • Enable internal teams with patterns, playbooks, and training.
High-level event-driven architecture for fintech payments platform
High-level architecture showing channel APIs, orchestration services, an event bus, and a central ledger service with dedicated reporting and reconciliation pipelines.
Execution

Phased migration that kept the business running.

Velinsa coordinated a phased cutover that reduced risk while delivering incremental value, starting with read-only shadow traffic and culminating in full blue/green releases.

1

Baseline & target state

Mapped current transaction flows, failure modes, and SLAs; defined target event-driven design.

2

Strangler services

Introduced edge services for authentication, routing, and idempotency without touching the core.

3

Event backbone

Implemented an event bus and ledger service, gradually moving critical workflows onto streams.

4

Cutover & optimisation

Rolled out blue/green deployments, tuned performance, and handed over with runbooks and training.

Impact

Measured outcomes across performance and operations.

5x
Increase in sustained transaction throughput
99.96%
Availability during and after migration
-60%
Reduction in incident volume related to releases
2 weeks
Typical time-to-market for new partner integrations

Exploring a platform rebuild or migration?

Velinsa can help you assess your current architecture, propose a target design, and plan a migration that balances risk, cost, and speed.

Talk to our platform team