Engineering Manager and Senior Software Engineer working across Python and React, with a focus on experimentation, performance, and Infrastructure as Code on AWS.
Physiotherapy patients had no simple way to manage their care and progress between sessions.
Founded and built the product — defining direction, designing the digital experience, and shipping the platform.
Still in MVP — built to keep physiotherapy patients engaged between sessions and give clinics a lighter way to manage recovery.
A specialized chronic-pain and mental-health clinic in Costa Rica — coordinating rheumatology, neurology, psychiatry, and physical therapy — needed a credible, search-visible website that earns patient trust and turns visitors into booked evaluations.
Designed and built the entire site solo in Next.js 16 / TypeScript — trilingual (ES/EN/PT), with SEO at its core to grow the clinic's patient base through search.
Organic search is the site's #1 channel — ~50% of users and 390 sessions in its first six months, ahead of direct and social.
Onsetto helps banks win a business's core operating account by automating the switch — which hinges on reliably parsing uploaded bank statements and on engineering foundations a fast-growing team can build on.
Built Auto Switch Click, one of Onsetto's core features — a one-click switch that moves a business's core operating account automatically — and hardened the statement parser for the messy real-world PDFs it couldn't handle.
Smoother onboarding for the whole dev team — and the work earned enough trust that I'm now building a new engineering team in Costa Rica.
The world's most popular survey platform runs on a large, long-lived codebase and cloud estate that has to stay reliable and maintainable as it scales across many AWS accounts.
As a Senior Software Engineer I modernized core platform components — AWS-native migrations, legacy refactors, and Terraform-managed infrastructure across multi-account environments.
More reliable, maintainable platform foundations — safer changes and cleaner infrastructure across the org's AWS estate.
A real-time fraud and risk platform needed modernized services, hardened inter-service security, and broader automated test coverage to scale safely.
Modernized Python services on the fraud and risk platform — hardening inter-service auth, expanding automated testing, and contributing ADRs, secure ADF data pipelines, and Grafana/Lambda observability.
A more secure, better-tested, and more observable fraud-and-risk platform — safer to change and scale.
I'm an engineering manager and software engineer based in Costa Rica — most at home where product, performance, and infrastructure meet.
I work across the stack in Python and React, and I care just as much about the systems underneath: reliable, reproducible infrastructure, clean data pipelines, and cloud foundations you can actually reason about. I like shipping fast — and then measuring honestly whether it worked.
Increasingly, that means leading as well as building. I'm drawn to small, accountable teams with clear ownership — the kind of structure that lets good engineers do their best work.
Everyone pictures the Pacific. Costa Rica's Caribbean coast — Limón, Puerto Viejo, Cahuita — runs on a slower rhythm, and it might be the best place to take a tech team to reset the pace of the work.
A practical, source-cited guide to taking a simple Python Lambda to production — idempotency, retries and dead-letter queues, cold starts, concurrency, observability, Terraform, and cost.
Why I built my own corner of the internet — and what I plan to write about, from AWS and Terraform to AI in software and the rainforests of Costa Rica.
Open to senior and staff engineering roles, and to interesting problems in between.
andres@montero.cr