Backend engineer in connected fitness

As a Senior Backend Engineer (m/w/d) for our Core services, you are at the heart of our technical ecosystem: you will architect and scale robust backend services, drive our core API platform forward and ensure high availability and performance across our distributed systems. You bring deep expertise in Java and relational data architecture, a pragmatic DevOps mindset and the drive to take on technical ownership with the potential to grow into a Team Lead role. Are you up for that challenge? Then we would like to welcome you to our team in Berlin

• You design, build, and maintain high-throughput, low-latency APIs and core microservices that power our global connected fitness ecosystem and integrate seamlessly with third-party systems.
• You work as part of our Core Platform squad to implement robust services, manage service-to-service communication, and guarantee zero-downtime reliability.
• You architect efficient, scalable data models and optimize queries using relational databases, primarily PostgreSQL.
• You containerize services with Docker, manage deployments, and ensure high availability, observability, and smooth operation across our infrastructure.
• You write well-designed, testable, and maintainable code adhering to clean architecture principles; you actively mentor team members through code reviews and pair programming.
• You take ownership of architectural decisions within the team and bring the drive to step into technical leadership / Team Lead responsibilities as the platform expands.
• You are a seasoned Software Engineer with 5+ years of commercial backend engineering experience, with a solid track record in designing and maintaining distributed backend systems.
• Deep, hands-on expertise in Java and the modern JVM ecosystem (e.g., Spring Boot).
• Strong hands-on knowledge of relational databases, with proven experience in PostgreSQL schema design, query optimization, and indexing.
• Strong working knowledge of Docker; comfortable working closely with deployment workflows, CI/CD pipelines, and modern container orchestration.
• Working knowledge of cloud environments (GCP preferred, AWS is welcome) and experience with event-driven patterns, message brokers (e.g., Pub/Sub or Kafka), and microservice communication protocols (REST, gRPC).
• Pragmatic problem-solver who thrives on technical autonomy, communicates complex technical trade-offs clearly, and has the mindset to guide and mentor peers toward engineering excellence.
• Use 10% of your time on learning topics of your choice (conferences, hackathons, internal and external events, videos, books or innovation project
• We don't just maintain; we evolve. Explore our Tech Radar to see our stack, and join us in building an AI-agentic, iterative, and incremental product culture where AI is a core accelerator of our development lifecycle
• Use state-of-the-art laptops (MacOS, Linux, Windows? Choose your weapon! Also choose your Distro!)
• Join our diverse and international team to collaborate with talented professionals from around the world - get some team insights
• Benefit from flexible working hours, home office possibilities and 30 days of vacation per year
• Train for free with EGYM Wellpass in several thousand sports and health facilities across Germany and/or alternatively use our in-house gym with EGYM products
• Get a variety of great discounted offers, from fashion to leisure, through our employee benefits portal
• Stay active and use our leasing bike offer for your way to work or in your spare time
• Use €60 per month flexibly for public transportation and a meal subsidy