At eBay, we’re changing the way the world shops and sells. Our platform empowers millions of buyers and sellers in more than 190 markets around the world. We’re committed to pushing boundaries and reinventing the future of ecommerce for enthusiasts. What You Will Accomplish End-to-End ML System Ownership: Own the design, development, and deployment of large-scale machine learning systems for advertising. Own critical components of advertiser guidance, ranking, or optimization systems, ensuring robustness, scalability, and measurable business impact. Problem Framing & Technical Leadership: Translate ambiguous business challenges into well-defined ML problems. Drive solution design, modeling strategy, and experimentation frameworks across projects. Advanced Modeling & Innovation: Develop and apply pioneering techniques in areas such as LLMs, recommender systems, auction optimization, and causal inference. Push the frontier of applied ML to improve advertiser outcomes and platform efficiency. Cross-team Influence: Collaborate across organizations (product, engineering, data, infra) to shape roadmaps and influence system design. Act as a key technical partner in defining long‑term advertising strategy. Research & External Impact: Drive high-impact research initiatives. Publish in top-tier conferences (e.g., KDD, WWW, NeurIPS) and represent eBay in the broader research community. Mentorship & Technical Leadership: Mentor researchers and engineers, provide technical guidance, and raise the overall bar of the team. Lead design reviews and promote innovative practices in ML development and experimentation. What You Will Bring Education: Ph.D. with 5+ years, or M.S. with 8+ years of experience in Computer Science, Statistics, Mathematics, or a related field. Deep Applied ML Experience: Proven track record of delivering impactful machine learning solutions in production at scale. Strong experience in advertising systems, recommender systems, search, or large-scale NLP/LLM applications. Technical Leadership: Demonstrated ability to lead sophisticated projects end-to-end, influence technical direction, and make architectural decisions. Advanced Technical Expertise: Expert-level proficiency in Python/Scala or similar. Deep experience with modern ML stacks (e.g., PyTorch, distributed training, LLM frameworks). Strong understanding of large-scale data processing (Spark, distributed systems). Experimentation & Causal Thinking: Experience designing online/offline experiments (A/B testing, causal inference) and translating results into product decisions. Communication & Collaboration: Outstanding ability to communicate with senior partners and influence multi-functional teams. Able to bridge research, engineering, and product effectively. Equal Opportunity Statement eBay is an equal opportunity employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, national origin, sex, sexual orientation, gender identity, disability, or other legally protected status. If you have a need that requires accommodation, please contact us at We will make every effort to respond to your request for accommodation as soon as possible. #J-18808-Ljbffr