Senior Data Scientist (AdTech)

TL;DR

Senior Data Scientist (AdTech): Developing and optimizing machine learning models for user behavior prediction and ad distribution with an accent on LTV, conversion, and deep learning at scale. Focus on owning the end-to-end ML lifecycle, implementing production-grade deep learning models, and maximizing advertiser ROAS.

Location: Hamburg, Germany (Hybrid: 3 core office days). Relocation support and visa assistance provided.

Company

hirify.global is an AI-powered mobile advertising company specializing in rewarded ad experiences and the Playtime channel for app publishers.

What you will do

• Translate complex product requirements into actionable machine learning solutions.
• Build robust models to predict user behavior, including LTV and conversion, to optimize retention and advertiser ROAS.
• Develop and deploy state-of-the-art deep learning algorithms for high-traffic production environments (>1M predictions per day).
• Own the end-to-end ML lifecycle: from extracting insights from terabytes of data to A/B testing and production.
• Collaborate with Backend, Infrastructure, and Analytics teams to ensure seamless model integration and system stability.
• Present findings and communicate the impact of ML solutions on product KPIs to business stakeholders.

Requirements

• 5+ years of professional experience in Data Science with a history of successfully deployed models.
• Strong proficiency in Python and core DS libraries: PyTorch/TensorFlow, Pandas/Polars, Numpy, Scikit-learn, and Gradient Boosting (LightGBM/CatBoost/XGBoost).
• Experience applying deep learning models in production environments with massive traffic.
• Advanced SQL skills and experience with distributed query engines such as AWS Athena, Trino, or Spark.
• Ability to explain complex mathematical foundations in simple, non-technical terms.
• Must be open to relocating to Hamburg, Germany.

Nice to have

• Experience in the AdTech industry.
• Technical knowledge of Airflow, model hosting, and deployment infrastructure.

Culture & Benefits

• Hybrid work model with 3 core office days and flexible working hours.
• Comprehensive relocation support, including visa assistance and a relocation bonus.
• 30 vacation days and 3 weeks of remote work per year.
• Professional growth through regular feedback and a dedicated development program.
• In-house gym with fitness classes, mental health support (EAP), and a central office with snacks and drinks.
• Active community with regular team events, company gatherings, and hackathons.