Senior Data Scientist (f/m/d) at adjoe GmbH

Hamburg, Germany

on-site · full_time · Visa sponsorship

Responsibilities:
- Architect, implement and iterate large-scale relevance and targeting models for real-time in-app bidding.
- Design and optimize bidding policies using Bayesian methods, reinforcement learning and other advanced optimization techniques.
- Build and deploy meta-learning and personalization frameworks that adapt from live user interactions.
- Lead A/B experiments and statistical analysis to validate hypotheses and measure impact on business KPIs.
- Take end-to-end ownership of models: prototype, productionize, monitor and maintain within our ML stack (Python, Kubernetes on AWS, Airflow, MLFlow, Trino).
- Collaborate closely with product, engineering and business teams; provide technical guidance and drive architectural decisions.

Requirements:
- 4+ years professional experience in Data Science, preferably in AdTech, mobile gaming, e-commerce or similar.
- Proven track record deploying ML solutions at scale, especially recommender systems and neural network models.
- Strong knowledge of Bayesian methods, reinforcement learning, experimentation and causal inference.
- Proficiency in Python and SQL; experience with Kubernetes, AWS, Airflow, MLFlow and Trino or similar tooling.
- Experience operating real-time, low-latency systems and evaluating model performance under production constraints.
- Excellent communication skills and ability to mentor others, participate in design debates and translate research into production impact.