Senior Data Scientist - Menu Personalization

Work with HelloFresh in Warsaw and its HelloTech organisation, HelloFresh’s global technology backbone with more than 1000 people, building the digital products that power our end-to-end food experience. From meal kits and ready-to-eat meals to specialty offerings like pet food and premium meat & seafood, HelloTech creates the platforms that bring tailored food solutions to millions of customers every month.

Our subscription-based, direct-to-consumer model relies on technology at every step, from customer-facing apps and personalization logic to pricing, forecasting, supply chain optimization, and initiatives that help reduce food waste. While our brands operate independently to serve distinct customer needs, they are united by shared platforms, data, and operational excellence built by HelloTech.

HelloTech works in autonomous, cross-functional alliances, each owning a specific product or domain end to end. By working with our Warsaw office, you will help shape scalable, data-driven products used across our markets, working with a modern tech stack and international teams to continuously improve how people discover, order, and enjoy HelloFresh’s products, today and in the future.

• Proven track record of scientific work (Bachelor's, Master's, or PhD) in computer science, statistics, physics, economics, mathematics, or data science.
• 3+ years of work experience as a data scientist focused on developing and deploying recommender systems or personalized ML models in a production environment.
• In-depth knowledge of various recommendation algorithms, evaluation metrics, and the practical challenges of maintaining a modern recommender system.
• Fluency in Python, including high familiarity with its scientific stack (Numpy, Pandas, Scikit-learn, Matplotlib). Experience in Databricks and PySpark is a plus.
• Technical proficiency in SQL for retrieving, manipulating, and analyzing large datasets.
• Experience with software development practices and tools such as Git, CI/CD, Docker, and AWS.
• Expertise in leveraging Generative AI tools (e.g., Claude, Copilot) to support model development, experimentation, and documentation.
• Exceptional communication capabilities to interact effectively with product managers, UX designers, and business stakeholders.

• Become an integral part of a high-impact team covering menu personalization.
• Contribute to designing and implementing the next generation of recommender models, from experimentation and data collection to operationalization.
• Shape the future of customer experience by proposing new personalization approaches and evolving statistical and ML models in pace with future company strategies.
• Design and execute A/B tests to measure the impact of new recommendation strategies on key metrics.
• Work with state-of-the-art technologies like AWS (EMR, Glue, S3, etc), Kafka, PySpark, Airflow, Databricks, MLFlow, and Claude (AI).
• Collaborate closely within other functions (data engineering, backend engineering, ML engineering, product) to translate business objectives into concrete strategies.
• Analyze the performance of models to understand customer behavior and implement technical improvements.
• Contribute to a collaborative and knowledge-sharing environment, providing technical guidance and coaching to team members and stakeholders.