Senior Backend Engineer Go - Payments Reporting

We believe in the everyday hero. Those who have the courage to follow their passion and who have the strength and determination to realise their dreams. Small business owners are at the heart of all we do, so we're creating powerful, easy-to-use financial solutions to help them run their businesses. With a founder’s mentality and a 'team-first’ attitude, our diverse teams across Europe, South America and the United States work together to ensure that small business owners can be successful doing what they love. About the team The Payments Reporting team sits at the heart of SumUp's financial infrastructure, building the systems that millions of merchants rely on every day to reconcile, report, and understand their money. We're in the middle of something genuinely exciting: building a reporting platform that serves both external integrators and internal teams at scale - delivering everything from file-based exports to real-time API reporting. This role exists because our ambitions have grown faster than our current team of three backend engineers can sustain alone, and we need someone who can take meaningful ownership of complex backend work, freeing the team to move faster on the architectural changes that matter most. What you'll do Build and maintain backend reporting features across Payout Reports, Payment Reports, Fee Invoices, and Transaction Reports Develop and own Reporting APIs (including Transaction History and Payout History) that serve both external integrators and internal clients Contribute to the migration of core payments functionality away from legacy systems, modernising the infrastructure that underpins our reporting platform Take ownership of the operational health of reporting services: monitoring, incident response, and performance optimisation Participate actively in planning and refinement sessions, bringing technical assessments and effort estimations to the table Support junior engineers through code reviews, pairing sessions, and knowledge sharing You'll be great for this role if you have: Strong experience building scalable, production-grade backend systems in Golang, with a solid grasp of concurrency patterns, goroutines, and channels Deep familiarity with software design principles - SOLID, common design patterns, and microservices architecture - and the experience to apply them pragmatically Hands-on experience with PostgreSQL or similar SQL databases, including query optimisation and database modelling Confidence working in Kubernetes environments, configuring and managing resources Clear, confident communication in English - written and spoken - and a collaborative approach to engineering: giving and receiving feedback openly Why you should join SumUp 🌍 Opportunity to work with SumUppers globally on large-scale fintech products used by millions of businesses worldwide, from our modern Sofia 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 in 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 you can be used to attend conferences and/or advance your career through further education 🏖 Generous time off: 25 days of paid leave, plus one extra day per year of service (up to 35) 🏥 Peace of mind: comprehensive health and life insurance - includes dental coverage 💪 Stay active: on-site yoga and a co-sponsored Multisport card offering access to hundreds of sports facilities 🍽 Meal support: benefit from a tax-free food voucher program (100 EUR per month) plus flexibility via our Re:Benefits platform (40 EUR) 🚌 Easy commute: free shuttle buses connecting directly to Joliot-Curie metro station 👶 Family-friendly: new baby bonus 🌴 Break4me: 1-month sabbatical after 3 years of service 🔗 Refer...