Machine Learning Engineer, Growth

Whatnot is a live shopping platform connecting buyers and sellers across diverse product categories. The Machine Learning Engineer will accelerate buyer growth by building and owning personalization models for user acquisition, activation, retention, and first-time buyer conversion. The role leads the full ML lifecycle and collaborates with product, engineering, data, and marketing stakeholders to deliver measurable growth outcomes.

Responsibilities:

• Lead the design, development, and productionization of ML models that power user acquisition, activation, and retention (e.g., ranking models, targeting systems, uplift modeling)
• Own the full ML lifecycle. Build and owndata pipelines, feature engineering, model training, deployment, and online experimentation. Build feedback loops from postbacks, conversions, and downstream revenue signals
• Identify and prioritize high-impact opportunities where machine learning can unlock growth, collaborating with product, engineering, data, and marketing stakeholders
• Drive technical excellence and establish ML best practices across the Buyer Growth team

Requirements:

• 5+ years of industry experience building and deploying ML systems at scale
• Demonstrated success in leading end-to-end ML projects that drove measurable business outcomes
• Deep expertise in personalization, ranking, or user modeling; strong intuition around user behavior in consumer products
• Advanced proficiency in Python, SQL, and common ML frameworks (e.g., PyTorch, TensorFlow, XGBoost)
• Strong communication and leadership skills; ability to influence roadmap and align cross-functional teams
• Experience building ML applications in E-commerce or Social products
• Prior experience in growth domains: user segmentation, retention modeling, large scale recommendation systems, notification ranking, etc