Senior Backend Engineer (Golang) - Bank Balance

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.
• Are fluent in 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

• 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.)