What you’ll do
- Develop new functionality and support existing services across the tribe’s codebase, primarily using Go.
- Contribute to the continued development of our in-house merchant risk decision framework, taking it beyond its MVP and enabling new fraud prevention, risk and compliance use cases.
- Design, build and maintain reliable distributed systems and backend services.
- Work closely with product managers, data scientists, machine learning engineers, fraud strategy teams and operational stakeholders to turn complex problems into practical solutions.
- Help shape technical direction, service boundaries and system design decisions across the team.
- Contribute to Python projects, including AI-agent initiatives, as you build a broader understanding of the team’s systems.
- Participate in code reviews, testing, monitoring and continuous improvement of production services.
- Use AI-assisted development tools thoughtfully to deliver meaningful features faster without compromising code quality, security or maintainability.
- Be open to participating in an on-call rotation as the team’s production responsibilities and support model evolve.
You’ll be great for this role if you have
- Professional experience developing backend software in Go or another language such as Java, C or C++; you’re motivated to learn and work with Go.
- Experience building and operating distributed systems and backend services
- Strong system design skills and an understanding of reliable, maintainable software architecture.
- Experience working with Kubernetes and Kafka
- Working knowledge of Python and/or an interest in contributing to Python-based products or AI/agentic development
- Experience using AI-assisted tools as part of your software development workflow
- Experience working in agile, cross-functional teams and collaborating with stakeholders beyond engineering
- A pragmatic, outcome-focused approach: you know how to define a valuable MVP, make sensible trade-offs and improve solutions iteratively
- A collaborative mindset and the confidence to challenge ideas constructively while remaining open to feedback
- Motivation to learn about fintech, fraud prevention, risk and compliance domains
Why you should join SumUp
🌍 Opportunity to work with SumUppers globally on large-scale fintech products used by millions of businesses worldwide, from our Sofia office. This involves an office-first setup
🧑🔬 We take learning and experimentation seriously with Hack Days every second Friday, and entire global Hack Weeks.
🌈 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
📚 A dedicated annual L&D budget of €2,000 for attending conferences and/or advancing your career through further education
🚀 Enrollment onto our VSOP program: You will own a stake in SumUp’s future success
🏖️ Generous time off: 25 days of paid leave.
🔄 30 Days Sabbatical: Enjoy the unique opportunity to take a well-deserved break with our 30 days sabbatical benefit after completing 3 years of employment with SumUp
🏥 Peace of mind: additional health insurance and life insurance
💪 Stay active: gym allowance
🔗 Referral Bonus: Earn additional rewards by referring talented individuals to join the SumUp team