Data Scientist (Recommendation Systems)

Location: Cologne, Germany; remote work is possible. Up to 20 work-from-home days per year can be taken anywhere in the EU.

Company

hirify.global operates a European e-pharmacy focused on helping customers discover and purchase health products through its webshop and app.

What you will do

• Improve product recommendation widgets by analysing customer behaviour and product data.
• Develop recommendation models using feature engineering and machine learning approaches such as collaborative filtering, ranking models, and embeddings.
• Lead end-to-end data science initiatives from exploration and experimentation through productionization, monitoring, and continuous improvement.
• Design and analyse A/B tests, define success metrics and guardrails, assess statistical uncertainty, and communicate recommendations.
• Work cross-functionally with Product Managers, ML Engineers, Data Engineers, MLOps, and domain experts.

Requirements

• Practical experience developing machine learning models, including data preparation, feature engineering, modelling, and evaluation.
• Strong Python and SQL skills, with familiarity with Git, testing, and reproducible development.
• Understanding of production model development, reproducible training, reliable data pipelines, and scalability and maintainability trade-offs.
• Practical expertise in A/B testing and experimental design, including metric selection, statistical power, and result interpretation.
• Solid understanding of recommendation systems and relevant machine learning methods.
• Ability to work iteratively in a cross-functional product environment and translate business goals into practical solutions.

Culture & Benefits

• Flexible work-from-home arrangements where the role does not require office presence.
• Up to 20 days per year working anywhere in the EU.
• 30 days of paid vacation per year plus an additional day for Rosenmontag.
• Optional unpaid vacation of up to 10 days after one year of employment.
• Training, development opportunities, Urban Sports Club membership, and team events.