Jeremias Lautaro Barrios Hermosa 👋

I work as a backend engineer with 4+ years of experience in fintech/payments, building services in Java + Spring Boot and distributed, event-driven architectures. I’m drawn to the hard problems: sensitive integrations, zero-downtime migrations, and systems that have to survive real-world traffic and edge cases. What I’ve been doing: - ACH payments: integrated ACH into a payment gateway, using Kafka, event-driven design, and TDD. - Monolith to microservices: contributed to an architectural evolution that improved overall performance by ~40%. - Payment plan architecture: designed/implemented a more maintainable and robust solution, reducing complexity (including removing 600+ lines of code). - Migrations & maintenance in financial software: upgraded libraries/components to reduce vulnerability risk; migrated Java 11 → 17 (80+ classes and 127 queries), cutting ~800MB of compute load. What defines me: pragmatism, ownership, and a healthy obsession with clean design and observability. When trade-offs show up, I make them explicit, measure them, and ship with a rollback plan.