Senior Data Scientist

RELOCATION TO GERMANY adjoe builds the technologies behind mobile apps growth and monetization. With our core product Playtime Arcade, we’ve become the global leader in rewarded advertising, an ad unit built on a simple premise: users earn real in-app rewards for engaging with new apps. The result is one of the most effective value exchanges in adtech, connecting advertisers and publishers with over 770 million users annually. Architecting Intelligence to Optimize 200M+ Daily Decisions As the intelligence core of our engineering organization, our Data Science team doesn’t just deploy models, we engineer the fundamental decision engine that powers our platform. At a scale of 770 million users and 100,000+ predictions per second, we are solving a multi-objective optimization problem that balances user incentives, advertiser ROI, and long-term platform health in real time. Our architecture is built on a 1PB+ behavioral data lake, providing the high-fidelity input necessary to train deep learning models that predict individual user engagement with precision. We aren’t just optimizing clicks, we are dynamically calculating optimal reward structures to sustain a global value exchange. Engineered for performance, our stack leverages Tensorflow and PyTorch for model training, NVIDIA Triton to achieve sub-100ms inference. We own the full ML lifecycle from high-level research and feature engineering to deployment and A/B experimentation. Here, you will find the autonomy, the data depth, and the massive scale required to solve the most complex optimization challenges in the adtech ecosystem. Your Mission & Who We Are Looking For: — Proven track record in production ML with 5+ years in Data Science and deployed models that moved real business metrics. — Building models that predict LTV, conversion, and user behavior across 770 million users, impacting advertiser ROAS and publisher revenue. — Deep learning as primary tool with strong hands-on experience in PyTorch or TensorFlow and production deployment handling 1M+ daily predictions. — Full ML lifecycle ownership from data extraction using Trino, Spark, or AWS Athena, through model development, A/B validation, to production deployment. — Experience with Airflow or model hosting is a strong plus. — Fluent in Python and data at scale, comfortable with pandas/polars, numpy, scikit-learn, LightGBM, CatBoost, XGBoost, and advanced SQL skills. — Ability to translate product requirements into ML logic and explain model behavior and impact to non-technical stakeholders. — AdTech experience is a strong plus. What’s in It for You? — Relocation support to Hamburg, Germany for worldwide talent. — Opportunity to build infrastructure behind impactful adtech platform reaching hundreds of millions of users and powering billions of decisions daily. — Ownership of projects impacting 770M users and pushing adtech boundaries. — Fast-paced environment with multiple daily solution deployments and learning from results. — Collaborative culture with diverse global team from over 40 countries. — Enjoy daily victories and energetic work environment.