Data Scientist - Search Retrieval (f/m/d)

Retrieval is the foundation of every search result. As a Data Scientist on our Search team, you'll own the algorithms (keyword, vector, and beyond) that surface the right products for every customer query. Your work has a direct, measurable impact on how customers discover products and experience our shop.

What you move

• Design, build, and improve retrieval passes for our product search, including keyword-based (e.g., BM25) and vector-based (embedding) search
• Develop hybrid retrieval strategies that blend lexical and semantic signals, including candidate merging and score normalization
• Continuously improve retrieval systems by evaluating performance and leveraging interaction data from millions of users
• Analyze search logs and user behavior to identify recall gaps, underperforming query segments, and long-tail query issues
• Bring models from prototype to production together with engineers, ensuring low latency and high availability at e-commerce scale

What you will bring

• mindestens 3 Jahre relevante Berufserfahrung
• Search / Information Retrieval / Machine Learning
• Completed degree (university / university of applied science / higher technical college)
• Data Science / Computer Science / Machine Learning
• English (Fluent)
• University degree in data science or a related field (MSc or PhD), as well as at least 3 years of relevant professional experience, ideally with practical experience in search or information retrieval
• Excellent Python knowledge including experience with machine learning libraries such as PyTorch, TensorFlow and scikit-learn
• Experience designing experiments and interpreting metrics for large-scale online systems (A/B testing, offline evaluation)
• Experience in handling large amounts of data, including advanced SQL knowledge and experience with database systems (e.g. BigQuery) for analyzing user interactions
• Experience in the field of MLOps, especially in the deployment and operation of machine learning models in production, e.g. with orchestration tools like Airflow or Dagster
• Solid command of English, both written and spoken; German is a plus
• Pragmatic, product-oriented mindset and good communication skills for working across disciplines
• A willingness to challenge «how things have always been done» and propose more efficient, automated or effective solutions
• Using creativity and initiative to solve problems and achieve goals

The benefits we offer

• Values, not empty words – Cooperative, innovative, piratesque, responsible, ambitious – these five values are what we practice and preach.
• Courageous thinking – We encourage everyone to think on their feet, and love it when they come up with bold or edgy ideas.
• Uncomplicated approach – Simplicity is at our core. We avoid the unnecessary and focus on what really matters – from overcoming challenges to celebrating our shared successes.
• Flexibility and freedom (Office Jobs) – We offer working-from-home options, up to 8 weeks of workation, and every position is possible with an 80% workload.
• Rapid growth – With us, growth is a continuous journey. We also support you with EDU Points (CHF 2,000 for employees in Switzerland, EUR 1,600 for employees in Germany, and EUR 700 for our Serbian employees) for your professional development, so there’s no risk of you getting stuck in a rut.
• More Benefits Switzerland – 25 days of holiday, exclusive employee conditions in our online shop, mobile, internet and TV plans at company rates and many other benefits.