Senior Software Engineer (Ruby on Rails)

PAIR Finance; Berlin; On-site; EUR 90,000 - 120,000; Full time

Benefits offered by this job

Company pension

Flexible hours

28 days leave

International team

Team events

Development opportunities

Modern office

Job summary

PAIR Finance seeks a senior software engineer to own end-to-end backend development within a fast-growing, AI-enabled platform. You will drive architecture decisions, build scalable services using Ruby on Rails alongside Go/Python, and work closely with product to shape the roadmap.

Strong English communication and an agile mindset are essential. You will join an international team and have opportunities for personal growth, with flexible hours and a modern office environment.

Qualifications

• 5+ years of professional software engineering experience.
• Strong backend experience in Ruby (Ruby on Rails).
• Experience with TDD and CI/CD.
• Ability to work independently with minimal hand-holding.
• Language-agnostic mindset; choose right tool for the job.
• Solid English communication skills.
• Interest in AI-based technologies.
• Experience in Agile environments (Scrum, Kanban).
• Infrastructure familiarity with AWS, Terraform, Docker, Linux.

Responsibilities

• Own a clear end-to-end scope: from idea to production, lead within the team.
• Design, build, and run POCs to de-risk decisions.
• Develop, optimize, and maintain core backend applications and services.
• Contribute to high-level architecture for scalability, performance, and security.
• Delve into the In-Court/After-Court domain and related debt collection processes.
• Collaborate with product to shape roadmap and drive growth.
• Leverage AI tools and contribute to AI-based platform evolution.
• Stay current with industry trends and bring ideas to the team.

Job description

• 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 In-Court/After-Court domain (the legal and procedural knowledge behind our
• Collection 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

Benefits

• Company pension and other benefits to add up to an excellent all-round package
• Flexible working hours and 28 days leave a year for a healthy work-life balance
• Good pay for strong performance
• An international team of professional colleagues and strong experts making up an inspirational network
• Team events for a successful team
• Individual development opportunities and a transparent, nurturing feedback culture for your own personal career path
• Challenging, varied tasks along a steep learning curve
• Modern office with fresh fruit, muesli and drinks to create a pleasant working environment

We’re looking for a senior software engineer who takes ownership end-to-end, is comfortable being the technical driver of a well-defined scope, and is energized by learning a deep, high-stakes domain: the legal processes around In-Court and After-Court debt collection5+ years of professional software engineering experience, including 1+ year on medium-to-large projectsStrong backend experience in Ruby (Ruby on Rails): this is our core stack, and required for the roleExperience with TDD and CI/CDProven ability to work independently: scope, drive, and deliver a project with minimal hand-holdingLanguage-agnostic mindset: you pick the right tool for the job (hands-on experience with Go and/or Python is a big plus)Solid English communication skillsGenuine interest in working with, and building on top of, AI-based technologiesComfortable in an Agile environment (Scrum, Kanban)A track record of writing clean, maintainable backend code and solid infrastructureExperience in the financial or accounting industryFrontend development experience, especially Vue.js and GraphQL knowledgeKnowledge of other backend technologies, such as Node.js, Rust, or JavaInfrastructure experience: AWS, Terraform (IaC), Docker, Linux