Senior Principal Applied Scientist - ZMS (all genders)

Role Senior Principal Applied Scientist – Drive the scientific vision and execution for the Bidding and Allocation engines within Zalando Marketing Services (ZMS). Lead optimization of real‑time ad‑tech decisions, combining high‑load low‑latency engineering, auction theory, mechanism design, large‑scale Bayesian inference, value‑based bidding, reinforcement learning and multi‑objective optimization. Responsibilities - Lead research and development of real‑time bidding and allocation algorithms, optimizing platform health, advertiser performance and user relevance. - Advance auction and mechanism design capabilities to ensure a fair, efficient, transparent marketplace. - Collaborate with Product Managers, Engineers and Analysts to translate complex business constraints into mathematical objective functions. - Define and execute the long‑term scientific roadmap for ZMS Ad Tech Bidding Optimization together with engineers and ML scientists. - Mentor and grow senior team members, acting as a force multiplier for the scientific community. Qualifications - PhD in Machine Learning with a strong publication record and industry experience. - Proven research excellence with peer‑reviewed publications in computational advertising, auction theory, mechanism design, game theory or equivalent impact. - 10+ years of experience (principal level) optimizing complex systems via automated algorithms in Ad Tech, marketplaces or related fields. - Deep expertise in optimization, control theory or reinforcement learning applied to bidding and budget pacing. - Expert knowledge of productionalizing ML models under ultra‑low latency constraints and large‑scale distributed systems. - Strong proficiency in Python and related stack; ability to architect scalable data pipelines for sparse, high‑dimensional advertising data. What We Offer - 27 days holiday (up to 30 with tenure) and 2 paid volunteering days. - Hybrid working model with up to 60 % remote and up to 30 days per year working from abroad. - Employee share program and 40 % discount on Zalando fashion/beauty products (30 % Lounge discount, external partner discounts). - Relocation assistance, family services and counseling. - Health and wellbeing options (Wellhub/Gympass) and mental health support and coaching. - Development opportunities through a training platform and biannual peer‑to‑peer review.