iOS Engineer - Design System

Role overview

As an iOS Engineer on the Design System team at SumUp, you will translate SumUp’s design language into a reusable, easy-to-use library of UI components and experience patterns. You’ll work closely with the Mobile Platform team and partner with product and design teams to help deliver consistent, accessible experiences at scale.

What you’ll do

• Shape core user and developer experience across SumUp’s iOS ecosystem
• Collaborate with product and design teams to build maintainable, consistent, and high-quality components
• Embed accessibility best practices into every component (e.g., VoiceOver, touch target sizing, color contrast, Dynamic Type)
• Provide hands-on technical guidance to product teams to deliver on company priorities (including a brand refresh)
• Review code contributions, enforce design system conventions, and mentor engineers on reusable UI development
• Lead migration of legacy UIKit-based components to SwiftUI while maintaining system stability
• Identify and address technical debt to uphold engineering excellence and codebase health

Requirements

• 3+ years of professional iOS development experience, ideally on large-scale or consumer-facing applications
• Fluent in Swift, with deep hands-on knowledge of both SwiftUI and UIKit
• Experience building or contributing to a design system, component library, or shared UI framework
• Strong accessibility skills: VoiceOver, Dynamic Type, color contrast, and touch target standards
• Testing knowledge for UI components: unit tests, snapshot tests, and UI automation
• Comfortable reviewing code and mentoring peers; able to give constructive feedback and raise team standards
• Self-motivated and structured; manage priorities and communicate clearly in English
• Genuine curiosity about the iOS ecosystem; keeps up with Apple releases and experiments with new APIs

Nice to have

• Direct experience with migration efforts from UIKit to SwiftUI in production systems