Responsibilities
- Own and lead end-to-end delivery of backend services for the Cards EU domain, including observability, testing, and production support.
- Contribute to architectural discussions and propose solutions for complex distributed-systems challenges.
- Write well-scoped pull requests, conduct code reviews, and maintain code quality and test coverage.
- Collaborate with adjacent engineering squads and product management to shape and refine the backlog.
- Participate in incident reviews and the on-call rotation while taking accountability for service reliability.
- Apply and champion AI tooling to accelerate engineering workflows and improve team AI literacy.
Requirements
- Hands-on experience delivering production-ready backend services end-to-end, including testing, monitoring, and maintenance, on a modern cloud-native stack.
- Production experience with Kotlin and openness to work with Elixir, Java, or Golang.
- Understanding of distributed systems, API design, data modelling, and relational databases.
- Hands-on experience with containerisation, orchestration, and CI/CD practices.
- Ability to define technical approaches for ambiguous product problems and lead implementation with minimal guidance.
- Ability to collaborate across teams and communicate clearly in professional English.
- Curiosity about the product domain and ability to consider user experience during feature refinement.
Benefits
- Office-first setup at SumUp's Sofia office, with global collaboration on large-scale fintech products.
- Virtual Stock Option programme.
- €2000 annual L&D budget and 10 paid days of educational leave.
- 25 days of paid leave plus one additional day per year of service up to 35 days, public holidays, and special leave options.
- Additional health insurance and life insurance.
- On-site yoga and a co-sponsored Multisport card.
- Tax-free food voucher programme and Re:Benefits platform.
- Free shuttle buses to Joliot-Curie metro station.
- One-month sabbatical after three years of service.
- Referral bonus programme.
About SumUp
SumUp is a leading global fintech company committed to levelling the playing field for small businesses. Founded in 2012, we’re the trusted partner of over 4 million merchants in 37 markets, providing simple and affordable tools that help them manage payments, finance, and customer relationships. Our vision is a world where everyone can build a thriving business. Guided by this, we champion small business ownership by creating accessible solutions that empower entrepreneurs to grow and succeed. Our diverse team of over 3,000 SumUppers — representing more than 90 nationalities across 20 offices worldwide — is at the heart of our success. Beyond business, we donate 1% of the net revenue generated by Solo devices to environmental causes and support educational and entrepreneurial initiatives around the world. Recognised as a Top Global Employer for inclusion by the Stonewall Workplace Equality Index in 2022 and 2023, and awarded Fintech Diversity Initiative of the Year at the Irish National Fintech Awards in 2025, SumUp continues to build an inclusive, supportive, and purpose-driven workplace where everyone belongs.