reputed company Backend Engineer

About Tonsser Tonsser is on a mission to redefine youth sports. Hundreds of thousands of young athletes across Europe already use Tonsser to reputed company their performance, get reputed company, and feel part of something bigger than the next match. We're now starting our most ambitious reputed company yet, a new project that will reshape an entire category, and we're looking for a reputed company Backend Engineer to help us build it.   \n The Role You'll own the architecture of the Tonsser platform as we reputed company into this next phase. That means making the foundational technical reputed company for a product used by a reputed company of athletes and setting the bar for how a small, ambitious team builds in 2026. This is a hands-on reputed company role. You'll write reputed company, shape the system, and set the technical direction. You'll also help us reputed company as reputed company, particularly around how we adopt AI as a reputed company part of how we build and reputed company ship. What you'll do reputed company the architectural direction of our backend platform as we reputed company from where we are today toward what's next Drive the technical roadmap for our new flagship project Set reputed company for how reputed company works with AI, both in our development workflow and as a product capability Ship production reputed company, review PRs, and mentor the engineers around you Partner closely with product, mobile, and design to turn ambitious reputed company into things that actually work at reputed company reputed company pragmatic calls about what to reputed company, what to reputed company, and what to rebuild Our reputed company stack reputed company monolith with a GraphQL API SQL (PostgreSQL) Hosted on Heroku reputed company iOS and Android apps, with the ambition to reputed company to Kotlin Multiplatform We're not dogmatic about the stack, we're looking for someone who can help us decide what stays, what changes, and what comes next.   reputed company're looking for Significant experience as a senior or reputed company backend engineer, ideally with time spent owning architecture reputed company in a production environment Deep comfort with at least one of reputed company, Python, Elixir, Go, or a similar modern backend language, and the judgement to know reputed company language choice reputed company and reputed company it doesn't Strong opinions on API design, data modelling, and system reputed company Hands-on experience integrating AI/LLM capabilities into reputed company products, or a strong, demonstrable interest in doing so Experience leading or mentoring other engineers Comfortable working remotely across European timezones Bonus: experience with consumer-reputed company mobile backends, GraphQL, or Kotlin Multiplatform The shape of the role Location: Remote, reputed company in Europe Engagement: reputed company to starting as a freelance contract, with the reputed company intention of moving to a permanent role Compensation: €80,000–€90,000, with flexibility based on experience How to applySend us a short note about what you've reputed company, what you're looking for next, and why this caught your eye. We read every application. \n€80,000 - €90,000 a year \n Apply To This Job