Senior Software Engineer (m/f/d)

At Credibur , we are building a debt management platform for non-bank lenders that must work reliably under real operational pressure. As our customer base and data volume grow, the hard problems are no longer features, but correctness, performance, and robustness. We are looking for an experienced backend-focused Software Engineer (m/f/d) who helps us stabilize and scale our core systems without unnecessary complexity. This role is about building practical, reliable solutions to real-world problems. Our hiring process includes a live coding session without AI assistance . Tasks Own backend robustness: Improve and maintain core backend components with a focus on correctness, performance, and long-term maintainability Solve complex business logic: Identify and fix edge cases caused by heterogeneous customer data and evolving requirements Improve database performance: Analyze and optimize slow queries, data access patterns, and schema decisions as data volume increases Build pragmatic solutions: Extend existing systems carefully, choosing simplicity over premature optimization & abstraction Collaborate on operations where it matters: Contribute to infrastructure, CI/CD, observability, and deployment improvements that directly impact backend stability and scalability Work closely with the team: Collaborate with other engineers and product to turn real operational needs into reliable backend behavior Requirements Proven experience as a Senior Software Engineer 2+ years of experience with Python in production systems 2+ years of experience with Django Strong problem-solving skills Hands-on experience with PostgreSQL, including data modeling and query optimization Experience designing and implementing RESTful APIs Proficient with Git and collaborative workflows (feature branches, pull requests, code reviews) Experience writing automated tests to ensure reliability and prevent regressions Ability to make pragmatic technical decisions, avoiding overengineering while maintai