Senior Backend Developer (all genders)

at  Freeletics GmbH

At Freeletics, we challenge and inspire people worldwide to become the strongest version of themselves—both physically and mentally. With over 56 million users, we’re revolutionizing fitness through AI-powered coaching, sports science, and long-term behavior change. Our personalized training plans and educational audio courses empower our community to build resilience, strength, and discipline.
To continue disrupting the health & fitness industry, we rely on a scalable, high-performance backend that serves millions of users worldwide. That’s where you come in.
We’re looking for a Senior Backend Developer who thrives in solving complex engineering challenges, improving performance at scale, and driving backend excellence. You’ll work at the intersection of technology, product, and data, helping us shape the future of data-driven fitness innovation.

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• Build & scale backend services that power AI-driven workouts for millions of users

• Architect, optimise, and refine backend systems to ensure high performance, scalability, and reliability
• Identify and resolve performance bottlenecks, propose improvements, and implement caching strategies
• Develop APIs and integrations that power our mobile and web applications
• Collaborate with cross-functional teams (UA, CRM, marketing, data) to align backend solutions with business goals
• Write clean, maintainable, and well-tested code while following best practices
• Improve observability & monitoring to ensure system health and uptime
• Contribute to DevOps processes, including CI/CD pipelines, Kubernetes, Docker, and AWS infrastructure
• Mentor and support other engineers through code reviews, knowledge sharing, and technical guidance