Backend Engineer (Java/Kotlin)

• Write code that is simple, readable, testable and maintainable
• Implement code reviews, give helpful feedback, actively contribute in team discussions and decisions
• Know the sweet spot between implementing beautiful and charming solutions which incorporate all existing software design patterns and just getting it done
• Suggest changes to our software that simplify the technical architecture of individual services or pay down technical debt
• Actively take over ownership for projects and collaborate with different teams across the organization
• Maintain existing services and contribute to developing the new solutions

Do you have experience in Software development?, Do you have a Bachelor's degree?, We are looking for a passionate and experienced Backend Software Engineer who loves working in a team and has a strong getting-things-done attitude., * 4+ years of professional software development experience in Java or Kotlin (mandatory)

• Computer Science fundamentals in algorithm design, data structures, problem-solving, and complexity analysis
• Knowledge and experience with database design
• Extensive experience with relational databases, including Postgres
• You are not dependent on libraries, but know when, where, and why you should use them (or not)
• Familiarity with CI/CD pipelines and comfort with build automation and dependency management tools like Maven
• A collaborative mindset and experience working across teams and functions
• Curiosity, openness to learning, and the confidence to step outside your comfort zone
• Clear, direct communication

• Feel comfortable in an environment where independence and new ideas are welcome
• Benefit from flat hierarchies and the greatest possible transparency so that things don't take longer than they have to and you always feel well informed
• Enjoy our centrally located office in Berlin (Erkelenzdamm 11 - 13, 10999 Berlin)
• Benefit from our family-friendly, flexible environment and paid child sick leave
• Bring your dog to the office: we love animals and want to cuddle yours, too!
• Use employee discounts on rebuy.de, sustainable products at Futurebens, offers for sustainable micro-mobility and massages directly in our office
• Have fun at our legendary team and company events
• Use our mental health offers as part of a cooperation with nilo
• Take care of your work-life balance with 30 vacation days
• Stay active with our own gym located directly in the building, making it easy to fit workouts into your daily routine.
• Benefit from an on-site daycare in the building, supporting a truly family friendly and flexible working environment.
• At rebuy all people are welcome and supported! We would like to talk, regardless of age, disability, national and social origin, skin color, religion, gender identity and sexual orientation. Just be who you are.

You will be part of a small but fun team of 4 people working on some of the most business-critical and technically interesting parts of rebuy's platform. Our scope covers AI-powered customer support automation, payment systems, and marketplace integrations (Amazon, eBay). We build on a modern, actively evolving stack, and we expect everyone on the team to use AI tools as a natural part of their workflow. Ready to become part of the most important mission on this planet? We are rebuy, pioneers in the sustainable reuse of electronics and media and we are looking for you! Our mission: to make circular living accessible to all, one transaction at a time. By giving products a second chance, we reduce resource consumption and avoid unnecessary e-waste. Our team of 500 comes from all corners of the world; we drive things forward collaboratively, take personal responsibility, value positive critical thinking, and persistently serve our customers and planet.