Gabriel Calin

I’m a Senior Node.js/TypeScript engineer focused on fintech and regulated, data-heavy backend systems. I bring long-term experience across B2B custody and payments platforms, with a strong bias toward reducing delivery risk in migrations, data-heavy APIs, and integrations.

Most recently, I worked as a Senior Backend Developer at Bitpanda, building an institutional crypto-custody platform for banks using Fastify, GraphQL, and TypeScript on AWS serverless. I owned key backend features end-to-end (including a regulated crypto address-book), strengthened authentication across services, and introduced testing patterns the team adopted.

Earlier, at RWE, I helped migrate legacy Java components toward NestJS services for an energy-market data platform, optimized MongoDB-backed filtering for 15,000+ daily queries, and improved production performance by cutting export time from 45 minutes to 12 minutes while reducing API response times by 65%. I also contributed frontend (React) in fully tested, distributed environments—balancing shipping speed with safety, quality, and maintainability.