Backend Engineer (Node.js)

Location: Copenhagen office, Denmark

The Global Bank tribe at SumUp, builds the financial tools that help small businesses manage their money more confidently, including Expenses and Making Tax Digital, two products that sit at the heart of SumUp's accounting and compliance offering. In this role you will join a small, senior squad, at a genuinely exciting moment: we starting with Making Tax Digital in the UK, where merchants can now submit Income Tax assessments digitally, SumUp's vision is to expand this into a full suite of Accounting tools - covering Income Tax assessment, VAT submission, and financial reporting across multiple markets. This is genuinely early-stage, high-impact work, and the Expenses and MTD squad is where it begins.

We are looking primarily for a Node.js backend engineer who can also contribute to React.js frontend work when needed. You'll work closely with two senior engineers, a Product Manager, a Designer, and an Engineering Manager - with the reach and resources of a global 200 person tribe behind you, and product impact at scale.

What you'll do

Build and maintain backend services and APIs for the Expenses and MTD products using Node.js and TypeScript

Contribute to backend development and API design, including building and refactoring services to support evolving product requirements

Contribute actively to backend services reliability within the squad, including CI/CD workflows, Kubernetes deployments, monitoring, and observability tooling

Collaborate with Product, Design, and cross-functional squads to deliver scalable, testable, and maintainable code

Participate in code reviews, contribute to architecture and technical decisions, and help evolve the squad's engineering practices

Contribute to the React.js frontend when needed by building and improving user-facing features and integrating backend APIs

You'll be great for this role if you…

Have solid proficiency in Node.js and TypeScript, with a track record of building and mai