Software Engineer

The Global Expansion Acquiring Squad is the engine behind SumUp's growth into new markets — integrating local payment acquirers, enabling merchant onboarding, and ensuring transactions flow reliably across countries like Mexico, Canada, New Zealand, and Australia. This role sits at the heart of that mission, owning critical backend systems while also shaping how the squad works.

What you'll do

• Design and build scalable backend services in Golang and Kotlin, covering merchant onboarding, transaction processing, and reconciliation across multiple acquirers and markets
• Lead technical investigations for new market launches and mentor engineers on the team
• Configure and maintain AI coding assistants (Cursor, Copilot, Continue) with team-specific rules, framework conventions, and testing patterns
• Build AI agents that automate repetitive development tasks, such as generating integration stubs, updating OpenAPI specs, and flagging idempotency violations
• Keep documentation accurate and AI-accessible, so the team spends less time answering "how does X work?" and more time shipping

What you'll need

• Strong proficiency in Golang (primary) or a JVM language such as Java or Kotlin, with experience building distributed, fault-tolerant backend systems
• Experience configuring AI coding assistants at a team level — defining rules, prompts, and context packages that produce consistent, framework-compliant output
• Solid understanding of idempotency, retry policies, and transaction safety in payment or financial systems
• Comfort working across multiple teams and domains simultaneously, navigating ambiguity and influencing without direct authority
• A track record of taking ownership in complex, cross-functional environments where the scope isn't always clearly defined

What they offer

• Virtual Stock Option programme — own a stake in SumUp's future success
• Annual L&D budget of €2,000 for conferences and professional development
• Corporate pension scheme with up to 20% match on 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