Machine Learning Engineer at whatnot

This role is designed for a seasoned Machine Learning expert with at least 8 years of experience building and productionizing ML systems, specifically within ads, search, or recommendation engines. The ideal candidate has a strong academic background (M.S./Ph.D. preferred) and the technical seniority to lead architectural decisions for high-scale retrieval and ranking funnels. The position offers a high-impact opportunity to shape the Ads Quality team’s technical roadmap. While "Mid-level" is noted in the metadata, the requirements suggest a Lead/Senior IC capacity with potential for future management. Benefits are standout, featuring a comprehensive "dogfooding" budget to use the app, extensive family planning and childcare allowances, and a gradual 16-week return-to-work policy for new parents. **You might be a good fit if you...** * Have 8+ years of experience using Python and PyTorch/LightGBM to solve complex marketplace problems. * Are comfortable owning the end-to-end ML lifecycle, from data orchestration (Dagster/Kubeflow) to low-latency inference. * Live within commuting distance of London and enjoy a "remote co-located" environment. * Prioritize business impact and user experience when designing experiments and success metrics.