Machine Learning Engineer, Growth

Role Description

The Buyer Growth team is responsible for driving Whatnot’s top-of-funnel growth and first-time buyer success. We're looking for a Machine Learning Engineer to accelerate buyer growth at Whatnot through intelligent, data-driven experiences. As the first ML engineer, you’ll build and own ML models personalization in onboarding and user targeting in our acquisition and engagement channels. This is a high-impact role on a team directly responsible for growing Whatnot’s buyer base and improving first-time user conversion.

• 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 model lifecycle: from data collection and feature engineering to model training, evaluation, deployment, and online experimentation.
• 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.

Qualifications

• 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.

Requirements

• 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.

Benefits

• Flexible Time off Policy and Company-wide Holidays (including a spring and winter break).
• Health Insurance options including Medical, Dental, Vision.
• Work From Home Support.
• Home office setup allowance.
• Monthly allowance for cell phone and internet.
• Care benefits.
• Monthly allowance for wellness.
• Annual allowance towards Childcare.
• Lifetime benefit for family planning, such as adoption or fertility expenses.
• Retirement; 401k offering for Traditional and Roth accounts in the US (employer match up to 4% of base salary) and Pension plans internationally.
• Monthly allowance to dogfood the app.
• Parental Leave: 16 weeks of paid parental leave + one month gradual return to work (company leave allowances run concurrently with country leave requirements which take precedence).