Senior Full-Stack Engineer - SuperApp

The SuperApp squad owns parts of the merchant experience across Web, Android, iOS and the flows that millions of small business owners use every day to run and grow their businesses. As our dedicated full stack web engineer within the squad, you'll own this space entirely, shaping technical direction, driving feature parity for SumUp's web experience. If you want real ownership, a broad scope, and work that lands directly in the hands of millions of merchants, this is the role. What you'll do: Own and develop core web dashboard features including the first-time user experience, home screen widgets, quick actions, tools section, and communications centre Build and maintain the backend services that power these flows, ensuring a seamless and consistent experience across web and mobile Work closely with iOS and Android engineers, product managers, and designers to shape cross-platform solutions and contribute to technical direction Lead the design and refinement of technical solutions — writing clear documentation, making architectural decisions, and communicating progress to stakeholders Be an active contributor to the web chapter and the broader engineering community at SumUp What we're looking for: Strong, proven experience with React.js and TypeScript, building scalable, maintainable applications in a production environment. Comfortable working across the stack, with experience building backend services or REST APIs, Go is a plus, but Node.js or similar is equally welcome. Ability to navigate and refactor complex codebases with a focus on clean, durable code and solid system design. Experience working in cross-functional teams alongside product managers and designers, with a strong sense of ownership and comfort with ambiguity. A product mindset, thinking about the merchant experience, not just the code, and connecting technical decisions to real business outcomes. Why you should join SumUp: 🌎 Opportunity to work with SumUppers globally on large-scale fintech products used by millions of businesses worldwide, from our Berlin office. This involves an office-first setup 🌈 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 of €2000 for your individual development, which can be used to attend conferences and/or advance your career through further education 💶 A corporate pension scheme where we match up to 20% of your contributions 🏖️ Generous time off: enjoy 28 days of paid leave plus public holidays and special leave days 🏋️ Numerous other benefits such as Urban Sports Club subsidy, Kita placement assistance, subsidised office lunches 🌴 Break4me: 1-month sabbatical after 3 years of service 🔗 Referral Bonus: earn additional rewards by referring talented individuals to join the SumUp team About SumUp Be empowered to do more that matters. At SumUp, we're on a mission to empower small businesses across the globe by providing simple and affordable tools that allow them to thrive. Today, over 4 million businesses in 37 markets rely on SumUp as their financial partner to manage payments, finance and customer relationships. Our commitment to small businesses is reflected in our diverse team of over 3,000 SumUppers from over 90 nationalities, united by global collaboration and an innovative mindset. Our core values lay the foundation for who we are and what we stand for, shaping our work culture and driving our success. We foster inclusivity and a continuous learning culture, providing a safe space for personal and professional growth. Our differences make us unique and strong as we strive to create an environment where everyone belongs and feels supported, no matter how they identify. SumUp is proud to be an Equal Employment Opportunity employer, actively seeki...