Senior Backend Developer (x,f,m)

Join us as a Senior Backend Developer and deepen your expertise in backend technologies while becoming a Subject Matter Expert in the complex chargeback domain. You will own backend APIs and systems that ensure secure, seamless transaction dispute resolution impacting millions of customers. This role offers the opportunity to lead technical improvements and grow within a collaborative, quality-driven team.

Responsibilities

• Own and enhance backend components of the chargeback process, ensuring high quality, performance, and stability.
• Deliver functional, well-tested code adhering to Clean Code principles, Test Driven Development, and Domain-Driven Design.
• Collaborate closely with frontend developers, product owners, QA, UX designer and other stakeholders to align API specifications and implementations.
• Proactively identify and reduce technical debt while implementing user-driven improvements.
• Lead and participate in technical deep dives and knowledge sharing to elevate engineering best practices.
• Mentor peers and contribute to cross-team problem solving and innovation.

Qualifications

• Proven experience in backend development using Kotlin and Spring Boot framework.
• Strong understanding of Domain Driven Design, Ports & Adapters (Hexagonal Architecture), and API design/validation.
• Experience with relational databases such as Postgres.
• Experience with container orchestration tools including Docker, Kubernetes and Helm.
• Prioritizing code quality and engineering excellence: you believe in the power of automated test suites and ideally embrace TDD as a core part of your development workflow to build scalable and bug‑free solutions.
• Excellent communication and collaboration skills to work effectively across teams and stakeholders.
• Ability to take ownership, deliver under uncertainty, and maintain attention to detail.
• Bonus: You have a Startup and/or Finance background.
• You're passionate about your work, but also know how to enjoy your free time!

Got the feeling not to match every single requirement? Don’t worry! We encourage you to apply anyways, even if your qualifications do not align perfectly. You might still be just the right candidate for us!

A place to stay together

From Morning Daily to Afterwork Drink, team spirit is essential to us. The heart of our togetherness is that we truly are connected with each other: We not only share fun & laughter, but also honest opinions - because that's how we grow: We exchange ideas, give support in our personal development, and celebrate success together! Besides our great community, we also offer numerous other benefits...