Senior Backend Engineer - Go

Sumup

At SumUp, the Global Bank team builds the core infrastructure and services that give merchants a digital bank account, helping small businesses manage their money easily and reliably.  The Balance Management Squad sits at the core of the Global Bank Platform. Right now, our team is completing a major milestone: consolidating and modernizing our balance management system in Europe. The next big step is creating a global transaction history service; a single, shared platform used by all regions to give merchants consistent and transparent views of their financial activity. As a (Senior) Backend Engineer, you’ll help modernize existing systems while balancing innovation with stability, collaborate with teams across regions, and build reliable services that manage diverse markets with different regulations. If you enjoy solving complex problems on high-load systems, are curious about banking, and are looking for a team that tackles challenges head-on, we’d love to hear from you. What You’ll Do * Build and evolve the SumUp’s core banking services that powers ledger operations and transactions, transforming our regional systems into a unified, scalable global platform. * Tackle complex distributed systems challenges, ensuring resilient services that continue to perform under high transaction volumes. * Support modernization initiatives by improving observability, adding test coverage, refactoring code for long-term maintainability, and gradually introducing new architectural patterns without disrupting live banking operations. * Contribute to key architectural decisions - build ledger and transaction history systems from the ground up, ensuring a globally scalable banking solution for our clients. * Collaborate with teams across Risk, Treasury, Finance, and Infrastructure to ensure smooth, compliant, and reliable global operations * Take ownership from design to production, running the services you build, monitoring their performance, and continuously improving how we deliver high-quality software at scale. You’ll be great for this role if * You have solid backend experience building reliable, high-volume services and you think carefully about system design, APIs, data modeling, and how services interact. * You are proficient in Golang and comfortable learning and working with other languages as needed, e.g. Kotlin or Elixir. * You write maintainable, well-tested code, follow CI/CD best practices, and take responsibility for the software you build from development to production. * You’re comfortable building, deploying, and running services in cloud environments like AWS using Docker and Kubernetes. * You’re eager to learn about relational databases that perform well under load and maintain data consistency. * You are a collaborator who enjoys working across regions, communicating clearly, exchanging feedback effectively, and making thoughtful technical decisions together. * You have a curiosity for building reliable financial services and banking domain It’s a plus if you have * Knowledge of Elixir - some of our legacy services are written in Elixir, and while it's not essential, it would be useful if you've worked with it before * Deeper PostgreSQL experience - we rely heavily on Postgres, so if you've done performance tuning, complex queries, or schema design, that's a plus * Experience with event streaming platforms (Kafka preferred) and modern observability stacks (Grafana, Honeycomb, etc.) Why you should join SumUp * Be part of a company that values diversity and celebrates unique perspectives. * Work with a global team of skilled professionals in an environment that fosters collaboration, learning, and growth. * Be part of a global tribe building a banking solution from the ground up and delivering impactful solutions to the real-life problems of millions of SumUp merchants all over the world * Career growth and learning opportunities: We invest in your development through regular training, mentorship programs, SumUp University leadership cohort and a yearly learning budget (2,000 EUR) * Sabbatical program for tenured SumUppers * Join a global team where you belong: Check out our D&I Initiatives and Employee Resource Groups such as Pride Club, SumAfro, Neurodiversity, Grupos Mais, Women in Tech, and more * Health & wellness benefits: in-house fitness classes, gym in the office, subsidized Urban Sports Club and available psychotherapy sessions * A lot of other benefits such as Subsidized Public Transport Card, Kita placement assistance, Pension Scheme, Language Learning platform/courses etc. * Enrollment onto our virtual stock ownership program - you will own a stake in SumUp’s future success About SumUp Be empowered to do more that matters. At SumUp, we're on a mission to empower small businesses across the globe by providing a vast set of simple and affordable business tools to help them start, run, and grow their businesses. Today, over 4 million businesses in 36 markets rely on SumUp as their financial partner to manage payments, finance and customer relationships. Our commitment to small businesses is reflected in our diverse team of over 3,000 SumUppers from over 90 nationalities, united by global collaboration and an innovative mindset. Our core values lay the foundation for who we are and what we stand for, shaping our work culture and driving our success. We foster an inclusivity and continuous learning culture, providing a safe space for personal and professional growth. Our differences make us unique and strong as we strive to create an environment where everyone belongs and feels supported, no matter how they identify. SumUp is proud to be an Equal Employment Opportunity employer, actively seeking and embracing diversity in our workforce. We don't make hiring or employment decisions based on race, colour, religion or religious belief, ethnic or national origin, nationality, sex, gender, gender identity, sexual orientation, disability, age or any other basis protected by applicable laws or prohibited by company policy. Our commitment extends beyond recruitment to creating a safe and respectful workplace where harassment of any form is strictly prohibited. Explore career opportunities with us and join a team driven by collaboration, innovation, and a shared vision of creating a world where everyone can build a thriving business. Discover more about our vibrant and inclusive work culture and how we work on our careers website, and follow our journey on LinkedIn and Instagram. Job Application Tip We recognise that candidates feel they need to meet 100% of the job criteria in order to apply for a job. Please note that this is only a guide. If you don’t tick every box, it’s ok too because it means you have room to learn and develop your career at SumUp.

Sumup

About the team: You’ll join SumUp’s Merchant Intelligence squad within the Engagement Mission — a newly formed team building foundational backend services that create a shared source of truth for product and merchant data across the business. The team is focused on two core services: * Product Catalogue Service — a global source of truth for all products SumUp sells across every market, including hardware, subscriptions, and software, as well as market-specific feature and settings configuration. * Merchant Intelligence Service — a centralized platform that aggregates merchant data from across the SumUp ecosystem, helping teams understand the full merchant journey through product adoption, hardware sales, health signals, support interactions, and marketing cohorts. By building these services, the squad is solving a company-wide challenge: product and merchant data is currently fragmented across multiple systems and teams, creating duplication, inconsistency, and reliance on manual workarounds. The Merchant Intelligence squad is building the platform foundations that will help teams across SumUp move faster and make better decisions with reliable, centralized data. As a Senior Backend Engineer, you’ll help design and build these services from the ground up. You’ll work closely with product, data, and engineering teams across SumUp to create scalable systems that are reliable, easy to integrate with, and valuable to a broad range of internal users.   What you’ll do: * Design, build, and evolve foundational backend services that create a shared source of truth for product and merchant data across SumUp, with a strong focus on scalability, reliability, and ease of adoption by internal teams * Develop and maintain robust APIs, data models, and integration patterns that enable teams across the business to access consistent and trustworthy product and merchant information * Build and improve data ingestion, aggregation, and event-processing pipelines that bring together signals from across the SumUp ecosystem into actionable merchant intelligence * Contribute to shaping the long-term architecture and strategy for the Product Catalogue and Merchant Intelligence services, helping establish platform capabilities that can be used across multiple systems and teams * Write high-quality, maintainable backend code following engineering best practices for testing, observability, and production readiness * Collaborate closely with product managers, data teams, and engineers across SumUp to identify needs, solve complex data challenges, and turn them into effective technical solutions * Work across squad and domain boundaries to support integrations, improve data consistency, and enable better internal tools, workflows, and merchant experiences * Help define engineering standards, technical direction, and ways of working in a newly established squad operating in a complex and evolving domain   You’ll be great for this role if you have: * Strong professional experience in backend engineering, building and operating reliable production systems * Solid experience with Golang and designing scalable backend services * Strong knowledge of API design, system design, and data modeling * Hands-on experience with Postgres or similar relational databases * Experience with AWS, Docker, Kubernetes, and infrastructure-as-code tools such as Terraform * Familiarity with event-driven architectures and message brokers such as RabbitMQ or Kafka * A strong ownership mindset, with the ability to work independently and navigate ambiguity * Clear communication skills and a collaborative approach to working across product, data, and engineering teams Why you should join SumUp: 🌍 Opportunity to work with SumUppers globally on large-scale fintech products used by millions of businesses worldwide, from our Berlin 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 🚀 Enrolment onto our VSOP program: You will own a stake in SumUp’s future success 💶 A corporate pension scheme where we match up to 20% of your contributions 🔄 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 🔗 Referral Bonus: Earn additional rewards by referring talented individuals to join the SumUp team 🚵🏾‍♂️ Numerous other benefits such as Urban Sports Club subsidy, Kita placement assistance, relocation assistance, subsidised office lunches SumUp is an Equal Employment Opportunity employer that proudly pursues and hires a diverse workforce. SumUp does not make hiring or employment decisions on the basis of race, colour, religion or religious belief, ethnic or national origin, nationality, sex, gender, gender identity, sexual orientation, disability, age or any other basis protected by applicable laws or prohibited by Company policy. SumUp also strives for a healthy and safe workplace and strictly prohibits harassment of any kind.   About us: Be empowered to do more that matters. At SumUp, we're on a mission to empower small businesses across the globe by providing simple and affordable tools that allow them to thrive. Today, over 4 million businesses in 36 markets rely on SumUp as their financial partner to manage payments, finance and customer relationships. Our commitment to small businesses is reflected in our diverse team of over 3,000 SumUppers from over 90 nationalities, united by global collaboration and an innovative mindset. Our core values lay the foundation for who we are and what we stand for, shaping our work culture and driving our success. We foster inclusivity and a continuous learning culture, providing a safe space for personal and professional growth. Our differences make us unique and strong as we strive to create an environment where everyone belongs and feels supported, no matter how they identify.  SumUp is proud to be an Equal Employment Opportunity employer, actively seeking and embracing diversity in our workforce. We don't make hiring or employment decisions based on race, colour, religion or religious belief, ethnic or national origin, nationality, sex, gender, gender identity, sexual orientation, disability, age or any other basis protected by applicable laws or prohibited by company policy. Our commitment extends beyond recruitment to creating a safe and respectful workplace where harassment of any form is strictly prohibited. Explore career opportunities with us and join a team driven by collaboration, innovation, and a shared vision of creating a world where everyone can build a thriving business. Discover more about our vibrant and inclusive work culture and how we work on our careers website, and follow our journey on LinkedIn and Instagram.   Job Application Tip We recognise that candidates feel they need to meet 100% of the job criteria in order to apply for a job. Please note that this is only a guide. If you don’t tick every box, it’s ok too because it means you have room to learn and develop your career at SumUp.

Urban Sports Club

MEET URBAN SPORTS CLUB We are among the leading platforms for sports and wellness in Europe, dedicated to inspiring people to live active, healthy lives. With just one membership we offer access to thousands of fitness and wellness experiences across the continent. But what truly sets us apart? We believe our people are at the heart of everything we do. If you’re curious about how we work, what we value and how you might grow with us, explore our Culture Hub & Career Opportunities. *Big news: Wellhub and Urban Sports Club unite!* Urban Sports Club is now a proud part of Wellhub, creating a global wellbeing ecosystem. Together, we connect 39,000 corporate clients and 97,000 wellness partners across 18 countries, offering millions of people even more ways to stay active and take care of their health. THE OPPORTUNITY  We are looking for an experienced Senior Backend Engineer to join our Foundation Engineering team. In this role, you won't just be building features for a single product; You will be crafting the very core services that power the entire Urban Sports Club ecosystem. The Foundation team sits at the heart of our engineering organization. We are responsible for application-level, system-wide services that enable our multi-million user base to interact with our platform seamlessly. Your initial focus will be taking ownership of our critical Identity & Authentication services and our core Search backend, with exciting plans to architect and scale a centralized Notification service in the near future. You will act as a force multiplier for our entire engineering department. By designing highly scalable, secure, and performant internal APIs and services, you will enable other product teams to build fast and deliver value to our users. If you love deep-diving into system design, solving complex architectural challenges at the application level, and working with Golang, this is the perfect place for you. This position will be based in Berlin. WHAT YOU WILL DO * Own Core System Services: Architect, develop, and maintain high-throughput, application-level foundational services, focusing initially on identity/authentication and our core search backend service. * Drive Technical Evolution: Design and implement future shared services that support our vision for scaling the platform. * Enable Engineering Teams: Build clean, robust, and well-documented internal APIs and developer tools that empower other product teams to build features rapidly and securely. * Write Exceptional Code: Deliver highly testable, maintainable, and secure Golang code, taking full operational ownership of the components your team develops. * Foster Best Practices: Actively participate in the Urban Sports Club backend cluster, championing strong system design, modularized architecture, and automated testing across the company. * Collaborate Across Boundaries: Work closely with product owners, tech leads, and other engineering teams to understand their requirements and translate them into scalable, domain-agnostic solutions. WHAT YOU WILL NEED TO SUCCEED * You have extensive industry experience as a Senior Backend Engineer developing, optimizing, and troubleshooting large-scale applications written in Go (6+ years) * You have a solid understanding of (or direct experience with) core foundational services like Identity/Authentication protocols (e.g., Keycloak, OAuth2, OIDC) and search engines. * You possess a deep understanding of data structures, algorithms, and distributed system design. You know how to build modular, high-volume services that remain performant under heavy traffic. * You have a track record of designing clean, secure, and developer-friendly internal APIs that scale across multiple engineering teams. * You are comfortable working within cloud ecosystems (GCP/AWS) from an application perspective, understanding how to leverage cloud-managed services efficiently. * You break down complex, abstract problems into elegant software solutions. You communicate effectively with technical stakeholders and love mentoring others. * Experience with PHP is a nice-to-have. We have some legacy context here, so a familiarity with PHP helps if you need to understand existing logic during modernizations or integrations - but your primary daily weapon will be Go. * You engage, inspire, and motivate the people you work with. We like to have fun while building the backbone of a platform that inspires healthy living. WHAT’S IN IT FOR YOU  * Work on cutting-edge tech and influence the future of our stack: explore our Tech Radar * We're open to relocation and providing support with our visa agency * Free Urban Sports Club L Pro Membership + Friends and Family Discount: Stay active with free membership, plus discounts for friends and family. * Flexible Work Model: Enjoy a hybrid work setup, balancing on-site and remote work options to fit your lifestyle. * Extended Remote Work Options: Work up to 120 days remotely within the EU, the UK, and Switzerland, including 30 days outside the EU. You’ll also have the option to desk-swap at our other European offices. * WorkOUT Life Balance: Take advantage of 30 days of paid vacation annually, plus two additional days for volunteering, flexible working hours, and complimentary access to our mental health provider Open Up. * Personal Development: Receive an annual budget of €1,000 for professional growth, with regular internal training sessions and weekly German and English language classes. * Engaging Team Culture: Participate in regular team and company events along with wellness initiatives that help you stay productive, healthy, and engaged in a hybrid work environment. Urban Sports Club is committed to providing a friendly, safe, and welcoming environment for everyone who applies for a position or already works with us, regardless of their sports preferences, gender, gender identity and expression, sexual orientation, disability, physical appearance, body size, race, age, or religion (or lack thereof).