Senior iOS Engineer

About the Role At Sum Up, we're on a mission to bring merchants and consumers closer together and help local communities thrive. With Sum Up Consumer, we're building a rewarding banking experience that connects people to the small businesses they love while enabling free transactions for our merchants.

Sum Up Consumer helps consumers manage their money with ease and get more from everyday spending. It offers seamless payment experiences and financial tools designed for modern life—spanning banking, cards, savings, and open banking.

This is a high-impact, hands-on engineering role where you'll own the development and quality of the Sum Up Consumer iOS application. You'll work directly on the features that consumers interact with every day, collaborating closely with Backend Engineers, Product Managers, Designers, and Android Engineers to deliver polished, reliable, and impactful mobile experiences.

What you’ll do Build and ship features across key consumer banking product areas—including KYC flows, card management, savings, open banking consent, and payment experiences.

Write clean, testable Swift code and participate actively in code reviews to uphold high engineering standards across the codebase.

Contribute to and evolve the iOS app architecture, including modularisation, dependency management, and scalability patterns as the product grows.

Own performance and reliability by monitoring crash rates, proactively identifying issues, and driving app stability before they impact consumers.

Maintain a culture of quality by writing unit and UI tests and contributing to the health of our CI/CD pipelines.

Collaborate cross-functionally with Backend Engineers on API design, Product Managers on roadmap priorities, and Designers on seamless user experiences.

What makes you great for this position

Strong proficiency in Swift and deep knowledge of the iOS framework (Objective-C knowledge is a plus).Solid understanding of RESTful API integration and experience working with backend engineers on API design.

Experience working with agile methodologies, CI/CD pipelines, and pair programming.

Deep care for user interaction, usability, and interface quality—you build things that feel great to use.

Ability to understand a large problem, design a solution, break it into deliverable chunks, and ship it independently.

Passion for clean, maintainable, and testable code and a genuine pride in your craft.

Mature, business-minded approach—balancing high-quality engineering with pragmatism in a fast-paced environment.

Self-driven and proactive nature, comfortable owning a domain with limited direct oversight.

Previous experience in payments, financial services, or fintech environments is a strong plus.

Why you should join Sum Upð Opportunity to work with Sum Uppers globally on large-scale fintech products used by millions of businesses worldwide.ð 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.ð Enrolment onto our Virtual Stock Option programme: you will own a stake in Sum Up’s future success.ð

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.ð¶ Competitive Health & Life Insurance:
Includes comprehensive cover (optical, dental) and Life Assurance (2 x your salary).ð Financial Future: A corporate pension scheme and a referral bonus for bringing in top talent.ð️ Generous time off: 28 days of paid leave plus public holidays and special leave days.ð Break4me: 1-month paid sabbatical after 3 years of service.ð Culture of Connection:
Attend global offsites and/or hackathons with your teammates.

About Sum Up Be  empowered to do more that matters. At Sum Up, we're on a mission to empower small businesses across the globe by providing a vast set of simple and affordable business tools to help them start, run, and grow their businesses. Today, over 4 million businesses in 36 markets rely on Sum Up as their financial partner to manage payments, finance and customer relationships.

Our commitment to…