Credit card app with 2FA

This is a corporate project. Due to confidentiality agreements, source code, real data, and sensitive details cannot be shared. The content below focuses on technical challenges, architectural decisions, and key learnings from the project.

Context

Mobile and web flows with guided onboarding and dual verification.

Problem

Manual processes and fragmented interfaces limited scale and introduced recurring inconsistencies.

My role

I mapped end-to-end flows with leadership, defined success metrics and led squads to build shared code plus clear guidelines for delivery.

Technical challenges

• Integrate legacy systems and internal APIs with limited availability.
• Reduce rework caused by incomplete or divergent records.
• Keep observability and fast rollback for critical batches.

Decisions and solution

I designed an event-driven architecture with Node.js workers, queues and synchronous validations where instant feedback was essential. The front end adopted reusable components aligned with the design system and baked-in internationalization.

Result/Impact

Processing times dropped by more than 60% and ops teams started relying on automated alerts instead of manual spreadsheets.

Stack

• Node.js / TypeScript
• React + Next.js
• Redis / PostgreSQL
• Observability with Grafana + Loki