Full Stack Engineer

About the role

This is a backend-leaning full stack role where you'll work on real, impactful problems that sit right at the centre of how merchants discover, buy, and manage SumUp's products. You'll own the end-to-end checkout and buying experience across SumUp's platforms, from self-service journeys to sales-assisted flows.

What you'll do

• Build and maintain frontend and backend components that power our checkout and purchase flows across self-service and sales-assisted channels
• Contribute to core commerce capabilities including subscription promotions, bundled offers, and order lifecycle improvements
• Help improve platform reliability and reduce technical complexity, addressing recurring issues and supporting ongoing migrations
• Work closely with product managers, designers, and engineers to deliver scalable, high-quality features across multiple markets
• Improve merchant-facing experiences, including better visibility into orders, invoices, and tracking information

What you'll need

• Solid experience building full stack applications, with a backend focus. Ideally comfortable with Node.js or Go, though we're open to other backend languages.
• Comfortable working with both relational and non-relational databases.
• Practical frontend experience working with React or Next.js, with the ability to write clean, typed code in TypeScript or JavaScript.
• Strong communication skills in English, both written and spoken, with the ability to give and receive clear, constructive feedback.
• A pragmatic approach to problem-solving — able to make sensible trade-offs, unblock yourself and others, and write clean, maintainable code.

What they offer

• Opportunity to work with SumUppers globally on large-scale fintech products from our Berlin office (office-first setup)
• Annual L&D budget of €2,000 for conferences and further education
• Corporate pension scheme with up to 20% matching of contributions
• 28 days of paid leave plus public holidays and special leave days
• Urban Sports Club subsidy, Kita placement assistance, subsidised office lunches
• 1-month sabbatical after 3 years of service