Freelancer profile translated to English.

Description

If your product handles money, sensitive data, or regulations, a frontend failure stops being a bug and becomes a business problem.

I have five years of experience developing interfaces precisely in that context: digital banking, wealthtech, and environments subject to MiFID II, where code reaches production supporting real financial operations.

How I can help you:

Product development in React and TypeScript, with an architecture oriented towards long-term maintenance, not just a quick fix.
Financial and regulated products: KYC flows, risk profiling, complex forms with strict validation, and investment portfolio visualization.
Modernization of legacy frontends: progressive migration to React without interrupting operations or halting the team.
Integration of AI into products and development cycles (LLMs, Claude, MCP, GitHub Copilot). Real adoption experience: I have trained nearly 100 bank developers to incorporate it into their daily work.
End-to-end development with Next.js and Supabase, from design to production deployment.

**How I work**: with my own judgment and direct communication. If I believe an approach will cause you problems later, I'll raise it before we start, not after billing. I deliver documented, tested code that your team can maintain without depending on me.

Industry field of expertise

Languages

Spanish
Native or bilingual
English
Fluent

Workplace preferences

Remote only

Primarily works remotely

Santander Digital Services
Senior Frontend Engineer
SOFTWARE PUBLISHING
April 2023 - Today (3 years and 4 months)
Madrid, Spain
Product development at the 100% digital bank of the Santander Group, in an environment of high regulatory demands (MiFID II) and real user scale.

Development of a client application in React and TypeScript, applying hexagonal architecture to decouple domain logic from the framework.
Optimization of initial load time by 80% and internal operations by 70%.
Unit and integration test coverage (Jest, React Testing Library) in code managing real financial operations: in banking, there's no such thing as "we'll fix it later".
Leadership of internal adoption of AI applied to development: design and delivery of continuous training workshops for ~100 developers on GitHub Copilot, Claude, Claude Code, and the MCP protocol.
React.js React.js Artificial Intelligence Frontend Development
Openfinance
Frontend Engineer
SOFTWARE PUBLISHING
February 2022 - January 2023 (11 months)
Valencia, Spain
Full-React development of a B2B wealthtech platform for investment portfolio management, used by financial institutions and their advisors.

Building the interface that the financial advisor uses during the interview with the investor: KYC flows, risk profiling, and suitability test. An interface designed to be filled out live, in front of the client, with no margin for error or ambiguous steps.

Multi-step forms with conditional logic and strict validation, in a context where incorrectly captured data is not a bug: it's a regulatory non-compliance (MiFID II).

Investment portfolio visualization: composition, positions, and evolution, with the precision and formatting rigor required by financial data.
Stack: React, TypeScript, reusable components, REST API consumption.
React.js Frontend Development
NTTDATA
Frontend Engineer
SOFTWARE PUBLISHING
March 2021 - February 2022 (11 months)
Sevilla, Spain
Development and refactoring of the "la Caixa" Social Work web portal on Liferay DXP, migrating the presentation layer to React components.

Integration of React within a production Liferay DXP portal: coexistence of modern components with the CMS's portlet architecture, without breaking what was already working or blocking the rest of the team.

Progressive refactoring of the interface of a high-visibility public corporate portal, prioritizing maintainability and visual consistency.

Work in a large consultancy environment with a corporate client: validation cycles, defined standards, and coordination with backend and design teams.
React.js Frontend Development Liferay