# Microfrontends for Mercado Libre's retail platform

By Valentin Galfré · 2024 · Frontend platform · https://galfrevn.com/work/mercadolibre

Role: Senior Software Engineer on the 1P (first-party) team.

From April 2024 to September 2025 I worked on frontend platform engineering on Mercado Libre's first-party retail team, the direct retail experience on Latin America's highest-traffic e-commerce platform. I was the most experienced engineer on the team and its technical referent, not its manager.

## Story

- **Problem.** Several teams shipped into the same retail surfaces, so every deploy depended on everyone else, and performance regressions on high-traffic pages were expensive at Mercado Libre's scale.
- **Solution.** I architected microfrontend systems with React so each team could own and deploy its slice independently, and drove the performance optimization work across the highest-traffic surfaces.
- **Outcome.** Teams gained independent deployments and a more modular codebase, modern web practices spread across the frontend teams, and engineers grew through code reviews and technical guidance.
- **Impact.** Independent team deployments and measurably faster high-traffic pages on the retail experience.

## The shape of a deploy

The problem was never the code. It was that every team's change waited for every other team's change, and when something broke on a page half of Latin America was looking at, finding the owner took longer than the fix.

The work was in the seams: one owner per slice of the page, a thin shell that owned routing, design system and telemetry, a contract small enough to fit in your head, and failure isolation so a slice that did not load rendered its fallback while the rest of the page kept working.

> **Rule.** Any runtime dependency between two teams' slices is a defect, even when it works.

## How the standards travelled

Independent deploys gave teams autonomy. Performance budgets in the pipeline kept that autonomy from turning into slow pages. Neither would have held without the same few review comments, repeated across teams until they were habits.

## Around the work

## Links

- [Mercado Libre](https://www.mercadolibre.com)