Senior Data Scientist - (Global Search, Consumer)

Description

The search services behind every platform are yours to shape: you will own the deep learning ranking models and lead the move to agentic ML research, where LLM coding agents run hundreds of overnight experiments and the strongest signals reach production as ranking gains.

Search covers more than 60 countries and 35 languages and handles over 80 million searches a day across four continents. The rankers you build decide what millions of customers see each time they open the app.

You will sit in the Consumer Team and work on the global customer experience. Your models affect how the company wins and keeps customers through personalized interactions, which supports customer satisfaction, global growth and profitability.

The company operates in around 65 countries, is headquartered in Berlin, and has been listed on the Frankfurt Stock Exchange since 2017, where it is part of the MDAX index.

Responsibilities

• Design, build and productionize deep neural ranking models (DCN-V2, MMoE, Two-Tower) for high-throughput, low-latency serving, owning them from offline experiments and evaluation through monitoring and ongoing improvement.
• Lead agentic ML research: direct LLM coding agents (e.g., Claude Code, Gemini) to iterate on feature engineering and Learning to Rank (LTR) architectures, set up overnight experiment pipelines based on the auto-research paradigm, and review the results of hundreds of runs to surface signals quickly.
• Raise ranker quality through feature engineering and architecture work using ranking signals, feature stores and embedding-based retrieval, and turn current research into production systems.
• Own monitoring for model drift, latency regressions and feature pipeline integrity, and respond fast when signals move off track in any market.
• Work with Backend Engineers, Data Engineers and Product Managers to ship end-to-end improvements, explain ML trade-offs to non-technical stakeholders, and help shape the team roadmap.
• Mentor junior and mid-level data scientists and set the bar for experiment rigor, code quality and agentic development practices.

Requirements

• A Master's degree in Computer Science, Mathematics, Physics or a related quantitative field, or a Bachelor's degree with 6+ years of work experience, plus 4+ years as a Data Scientist or Machine Learning Engineer applying ML in high-traffic production systems.
• Hands-on experience shipping deep learning ranking architectures (DCN-V2, MMoE, Two-Tower), including multi-task learning, cross-feature interactions and embedding optimization at scale. You also need a solid grasp of LTR methods (pointwise, pairwise, listwise), offline metrics (NDCG, MRR), and why offline gains often fail to carry over to online A/B results.
• Strong working skill with LLM coding agents and agentic CLI tools (e.g., Claude Code, Gemini) for generating experiments, prototyping architectures and iterating quickly. Familiarity with the auto-research paradigm and willingness to review large volumes of generated results.
• Expert Python across the ML ecosystem (PyTorch, TensorFlow, scikit-learn), working knowledge of SQL (dbt), GCP or AWS, and big-data tools (PySpark, Scala). Hands-on MLOps across the lifecycle: feature stores, vector databases, model versioning and registry, Metaflow, CI/CD for ML, experiment tracking, A/B frameworks, low-latency deployment and production monitoring for drift, latency and data quality.
• Ability to turn broad business goals into well-scoped data science projects and take responsibility for outcomes, not only outputs.
• Experience in cross-functional, globally distributed teams and the ability to explain model behavior, experiment results and trade-offs to both technical and non-technical audiences.

Conditions

Hybrid working model with 2 days a week on site at the Berlin campus.

27 days of holiday, plus an extra day in the second and third year of service.

Equal-opportunity employer; applicants are assessed regardless of race, religion, color, national origin, gender identity or expression, sexual orientation, age, marital or disability status, or other personal characteristics. Accommodation requests can be sent to the Inclusion Officer.

Benefits may differ for interns, working students, fixed-term and part-time roles.

Benefits

• Health checkups, meditation and gym support.
• Educational budget of 1.000 €, language courses, parental support, and access to the Udemy Business course platform.
• Employee share purchase plan, sabbatical bank, public transport ticket discount, life and accident insurance, and corporate pension plan.
• Digital meal vouchers and food vouchers.
• Relocation support for moving to Berlin, including a relocation hub and guides.