iOS Engineer - Design System

Title: iOS Engineer - Design System Location: London, England, United Kingdom

About the team:

As an iOS Engineer on the Design System team, you'll translate SumUp's design language into a reusable, easy-to-use library of UI components and experience patterns — empowering product teams to build cohesive, accessible user experiences at scale.

The Design System team works hand-in-hand with the Mobile Platform team to set standards and provide guidance across all product teams at SumUp. As we expand our ecosystem of merchant and consumer-facing products, this role offers a rare opportunity to shape the foundation that helps developers build faster and ship higher-quality experiences to millions of users worldwide.

What you’ll do:

• Shape the core experience for both users and developers interacting with SumUp's iOS ecosystem
• Collaborate closely with product and design teams to build components that are maintainable, consistent, and beautiful
• Embed accessibility best practices into every component — from content descriptions and touch target sizing to color contrast and dynamic type
• Provide hands-on technical guidance to product teams to deliver on company priorities, including the upcoming support for landscape orientation
• Review code contributions, enforce design system conventions, and mentor engineers on best practices for reusable UI development
• Lead the migration of legacy UIKit-based components to SwiftUI while maintaining system stability
• Proactively identify and address technical debt to uphold a high bar for engineering excellence and codebase health

You’ll be a great fit for this role if you:

• Bring 3+ years of professional iOS development experience, ideally on large-scale or consumer-facing applications
• Are fluent in Swift, with deep hands-on knowledge of both SwiftUI and UIKit — and a clear view on when and how to use each
• Bring experience building or contributing to a design system, component library, or shared UI framework, and understand what it takes to make components truly reusable and scalable
• Take pride in crafting accessible user experiences — you know your way around VoiceOver, dynamic type, color contrast, and touch target standards, and treat accessibility as a first-class concern, not an afterthought
• Bring a strong grasp of testing best practices for UI components, including unit tests, snapshot tests, and UI automation
• Are comfortable reviewing code and mentoring peers — you enjoy sharing knowledge, giving constructive feedback, and raising the bar for the whole team
• Are self-motivated and structured in your working style — you manage your own priorities, communicate clearly in English, and thrive in a cross-functional, collaborative environment
• Stay genuinely curious about the iOS ecosystem — you follow Apple's releases closely, experiment with new APIs, and are excited to bring fresh ideas back to the team

Why you should join SumUp:

🌎 Opportunity to work with SumUppers globally on large-scale fintech products used by millions of businesses worldwide.

🌈 Commitment to Diversity and Inclusion: be part of a workplace that values and promotes diversity, fostering an inclusive environment where everyone's perspectives are respected and embraced.

🚀 Enrolment onto our Virtual Stock Option programme: you will own a stake in SumUp’s future success.

📚 A dedicated annual L&D budget for your individual development, which can be used to attend conferences and/or advancing your career through further education.

💶 Competitive Health & Life Insurance: Includes comprehensive cover (optical, dental) and Life Assurance (2 x your salary).

💰 Financial Future: A corporate pension scheme and a referral bonus for bringing in top talent.

🏖️ Generous time off: 28 days of paid leave plus public holidays and special leave days.

🌴 Break4me: 1-month paid sabbatical after 3 years of service.

🎉 Culture of Connection: Attend global offsites and/or hackathons with your teammates.

About SumUp

We believe in the everyday hero.

Small business owners are at the heart of all we do, so we're creating tools that help them run their businesses. With a founder’s mentality and a 'team-first’ attitude, our diverse teams across Europe, South America and the United States work together to ensure that the small business owners we partner with can be successful doing what they love.

SumUp is an Equal Employment Opportunity employer that proudly pursues and hires a diverse workforce. SumUp does not make hiring or employment decisions on the basis of race, colour, religion or religious belief, ethnic or national origin, nationality, sex, gender, gender identity, sexual orientation, disability, age or any other basis protected by applicable laws or prohibited by company policy. SumUp also strives for a healthy and safe workplace and strictly prohibits harassment of any kind.

SumUp will not accept unsolicited resumes from any source other than directly from a candidate