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Agent guide: [/agents.md](https://www.wearedevelopers.com/agents.md). --- # Senior Data Scientist - **Company:** EGYM GmbH - **Location:** Berlin, Germany - **Experience:** Expert - **Contract:** Permanent contract - **Skills:** Java (Programming Language), Application Programming Interfaces (APIs), Artificial Intelligence, Data Analysis, Computer Programming, Python (Programming Language), Machine Learning, NoSQL, Open Source Technology, Recommender Systems, Software Engineering, SQL Databases, Unstructured Data, Large Language Models, Prompt Engineering, Backend, Low Latency - **Published:** June 28, 2026 - **Apply:** https://www.xing.com/jobs/berlin-senior-data-scientist-155646937 ## About the Role * Experience: You bring 5+ years of experience delivering machine-learning-based solutions, ideally in personalization, recommender systems, or decision-support products * Programming & Data: You write production-ready Python and work confidently with structured and unstructured data across SQL and NoSQL databases; you're comfortable collaborating with backend engineers working in Java * ML & LLMs: You have strong ML fundamentals and hands-on experience building and evaluating LLM-powered features or agents (prompt design, retrieval, tool use, multi-step flows, defining quality criteria, building test sets, running automated and human evaluations, and doing error analysis). You're also familiar with adapting local/open-source models and understand trade-offs in size, serving, performance, and cost * Hybrid Approaches: You're comfortable combining classical ML and LLMs (e.g. for scoring, ranking, recommendation, or as components in larger decision systems) * Communication & Ownership: You explain complex topics clearly, work effectively with different stakeholders, and see problems through from definition to production launch ## Description Put your data science and machine learning talent behind a good cause and help make the world a healthier place by developing the next generation of product innovations at EGYM. You will take a leading individual-contributor role on EGYM Genius - the engine that powers personalized training plans for our users - combining LLMs, classical machine learning, and agentic systems from idea all the way to production. Apply now as a Senior Data Scientist (m/f/d) and be part of our Data Science team in Munich or Berlin. * Model Development: You use EGYM's diverse training and health data to build machine-learning models that support effective and healthy workouts * Data Exploration: You analyze complex datasets, validate hypotheses, and develop new approaches for challenging problems * LLM & Agent Design: You design and maintain LLM-based components and agents that reason over user context, call tools/APIs, and orchestrate multi-step flows to generate, adapt, and explain training plans * LLM Evaluation: You set up robust evaluation pipelines for LLM features and agents (golden datasets, automatic metrics, human evals, regression checks, and safety/guardrail tests) * Local & Open-Source Models: You are comfortable going beyond "just an API" - you can work with local/open-source models (running them on our infrastructure, adapting or fine-tuning them, and balancing quality, latency, and cost) * Collaboration: You work closely with Software Engineering and Product Management while sharing feasibility insights and ongoing results * Implementation: You develop solutions in a dynamic software environment aligned with the EGYM Tech Radar * Innovation Monitoring: You track advancements in AI and machine learning to ensure our solutions remain state-of-the-art, * Cross-Functional Experience: You complete a rotation in a software development team and collaborate directly with engineers * Impact Contribution: You deliver visible product improvements and optimize your work using real usage feedback * Process Optimization: You help us to standardize how we build and ship models and LLM agents - defining reusable evaluation suites, automating training and deployment steps, and setting up monitoring for quality, drift, and safety * Product Partnership: You act as a sparring partner for Product Management and help extend our product vision ## Related Videos - [Leveraging Real time data in FSIs](https://www.wearedevelopers.com/videos/806-leveraging-real-time-data-in-fsis) - [Developing the Backend with Stefan Lingler, CTO at Shpock](https://www.wearedevelopers.com/videos/100360-developing-the-backend-with-stefan-lingler-cto-at-shpock) - [Swapping Low Latency Data Storage Under High Load](https://www.wearedevelopers.com/videos/746-swapping-low-latency-data-storage-under-high-load) - [Data Science in Retail](https://www.wearedevelopers.com/videos/586-data-science-in-retail) - [NoSQL Data Modeling for Front-end Developers](https://www.wearedevelopers.com/videos/297-nosql-data-modeling-for-front-end-developers) - [How We Built a Machine Learning-Based Recommendation System (And Survived to Tell the Tale)](https://www.wearedevelopers.com/videos/752-how-we-built-a-machine-learning-based-recommendation-system-and-survived-to-tell-the-tale) ## Related Articles - [What Are Large Language Models?](https://www.wearedevelopers.com/magazine/304-what-are-large-language-models) - [The Most Popular IT Jobs on the Market](https://www.wearedevelopers.com/magazine/376-the-most-popular-it-jobs-on-the-market) - [Best Coding Boot Camps in Germany](https://www.wearedevelopers.com/magazine/237-best-coding-boot-camps-in-germany) - [The Biggest German Tech Companies](https://www.wearedevelopers.com/magazine/424-the-biggest-german-tech-companies) - [Data Analyst Salary Germany](https://www.wearedevelopers.com/magazine/277-data-analyst-salary-germany) - [7 Most Popular Web Developer Jobs in Europe](https://www.wearedevelopers.com/magazine/163-7-most-popular-web-developer-jobs-in-europe)