Senior Software Engineer - Ruby on Rails

• Own a clear scope end-to-end: take initiative from idea to production largely independently, and lead within your team (T-shaped: you go deep on your slice, and pair with one other developer)
• Design, build, and run POCs quickly to de-risk decisions before committing to a full build
• Develop, optimize, and maintain our core backend applications and services
• Work on high-level architecture to ensure scalability, performance, availability, and security
• Go deep on the domain (the legal and procedural knowledge behind our processes is a core part of the job, not a side detail)
• Collaborate closely with product to shape the roadmap and unlock further company growth
• Work AI-augmented: you already use (or are ready to adopt) tools like Claude Code as part of how you build, review, and ship
• Help evolve and enhance our AI-based platform
• Stay current with industry trends and bring ideas back to the team

• 5+ years of professional software engineering experience, including 1+ year on medium-to-large projects

• Strong backend experience in Ruby (Ruby on Rails): this is our core stack, and required for the role

• Language-agnostic mindset: you pick the right tool for the job (hands-on experience with Go and/or Python is a big plus)
• Proven ability to work independently: scope, drive, and deliver a project with minimal hand-holding
• Experience with TDD and CI/CD
• A track record of writing clean, maintainable backend code and solid infrastructure
• Comfortable in an Agile environment (Scrum, Kanban)
• Genuine interest in working with, and building on top of, AI-based technologies
• Solid English communication skills

Nice to have:

• Experience in the financial or accounting industry
• Frontend development experience, especially Vue.js and GraphQL knowledge
• Infrastructure experience: AWS, Terraform (IaC), Docker, Linux
• Knowledge of other backend technologies, such as Node.js, Rust, or Java

• For this senior-level role, our salary band is €77,000 - €90,000 gross per year (based on a 40-hour work week). The exact offer will reflect your experience and qualifications
• We offer visa sponsorship
• Thriving, financially stable company
• Strong experienced international team to support and mentor you along the way, smooth onboarding process
• International team of 30+ nationalities with professionals and experts
• Flat hierarchy, transparent and appreciative feedback culture, monthly all hands meetings, annual feedback and evaluation cycle, regular 1-on-1s with your lead
• Well-structured onboarding process as well as supportive and welcoming colleagues
• Personal learning & development budget as well as German and English language courses
• Unlimited employment contract, flexible working hours and 28 vacation days for your work-life balance
• Company pension plan, partly covered Deutschlandticket (public transport) and access to “Corporate Benefits”-voucher platform to ensure your full well-being
• Fun company summer and Christmas parties as well as regular team events
• This role is based in Berlin, and we have a hybrid working policy. Modern office near Uhlandstr. is complete with fresh fruit, muesli and drinks for a comfortable and enjoyable workplace

We are rethinking debt collection with our digital debt collection solution, characterized by our high customer orientation and efficiency standards. By using artificial intelligence, we are combining technology with behavioral science and so we are able to contact customers individually and in a simple way throughout the entire collection process.

Strengthened by one of the most renowned private equity firms in the fintech sector, Pollen Street, as well as partnerships with other investors such as Zalando Payments, PAIR Finance offers an excellent opportunity to dive deep into and actively shape the fintech industry.