UI Engineer II

Lisbon💼 Full-time🗓 2026-07-07 → 2026-09-26

Core

Build scalable mobile app architecture, navigation systems, and design infrastructure for Mollie's merchant-facing products to ensure seamless, accessible, and high-quality user experiences.

Role type

Senior UI Engineer (Mobile & Web)

Builds

Mobile applications (iOS/Android), web interfaces, and shared design systems for merchant payment and money management tools.

Domain

Fintech / Payments / Mobile Development

Deliverable

production ML models | product features | dashboards & analysis

Required skills

React, React Native, JavaScript (low-level fundamentals), CSS, CI/CD pipelines, REST API design, test-driven development, accessibility standards, design system ownership

Preferred skills

Native browser APIs, product-first mindset, end-to-end ownership, generalist technical approach

Technologies

React, React Native, JavaScript, CSS, CI/CD tools

Responsibilities

Scale mobile app architecture for growing user demand; own and evolve the UI design system for web and mobile; rebuild navigation architecture; improve app accessibility; strengthen testing practices and automation; build reusable patterns and tooling for cross-domain engineers.

Seniority

Senior, hands-on IC

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About Mollie

Financial Services1168Amsterdam, North Holland, NLFounded 2004

Mollie offers a single platform for businesses to get paid and manage their money. One that makes payments, reconciliation, reporting, fraud prevention, and financing simple for all – from startups to enterprises. Founded in 2004, Mollie’s mission is to make payments and money management effortless for every business in Europe. Our 850-strong team works from offices across the continent, including Amsterdam, Ghent, Lisbon, London, Maastricht, Milan, Munich, Berlin, Kiel and Paris. Today, more than 250,000 businesses use Mollie to drive revenue, reduce costs, and manage funds.