Senior Ruby on Rails Backend Engineer

Senior Software Engineer (Ruby on Rails) — help shape the future of retail work in Europe SameSystem is the leading Workforce Management platform for retail, used by 250,000+ people across 15,000+ locations in 24 markets. For over 15 years, brands like Bestseller, Pandora, IKEA, Magasin, Matas, Søstrene Grene, and Normal have relied on us to build fairer schedules and run smarter operations. We're growing fast across Europe, and with our Next-Gen Planning platform we intend to become the industry leader. Next-Gen Planning combines algorithmic solvers, machine-learning forecasting, and LLM-driven employee communication to let thousands of shops run their planning fully automatically. All of it runs through our main application, built in Ruby on Rails — and that's where we need strong backend developers. You'll work closely with the specialists behind the solvers and models, and build the Rails backend that turns their work into one product. What you'll do Turn complex retail-operations requirements into well-reasoned solutions, weighing the trade-offs of each design choiceOwn the Rails application at the heart of our platform - the layer that ties together backend services, solvers, ML forecasting, and LLM-driven features into one coherent productWork closely with the specialists behind those systems to design clean, reliable interfaces between Rails and everything around itWrite performant, scalable, well-tested code across the full lifecycle — from architecture and design through delivery and maintenanceAdvise teammates and leadership on how to make the product better and the codebase healthierShare what you learn, and help raise the bar for the whole team What we're looking for Several years building production applications in Ruby on RailsA strong grasp of design patterns and a genuine care for tested, maintainable codeCuriosity about micro-services, service architecture, and cloudSolid technical and analytical instinctsNice to have: JavaScript, React, GraphQL, Selenium, or Playwright What you'll get Competitive salary from DKK 60,000/month, plus pensionA place where good ideas ship fast and innovation actually drives the roadmapReal room to grow, in a team that values expertise and collaborationA high-trust, flexible culture with plenty of freedom in how you workSocial life beyond the desk: employee-run clubs (sauna, sports, food tours, etc.) and regular partiesUnlimited snacks, fruit, coffee, soda, energy and protein drinks Practical Location: Rentemestervej 2A, 2400 København NVTeam: You'll be part of a Business-team with a Product Manager, and a Backend-team with a teamlead - the teamlead is your direct manager