Fullstack Engineer, Seller Growth

Whatnot is the largest livestream shopping platform in North America and Europe, enabling sellers to turn their hobbies into businesses. The Fullstack Engineer in the Seller Growth Product Pod will design and build systems for fraud protection, seller onboarding, and growth experimentation, ensuring the sustainability and scalability of seller growth initiatives.

Responsibilities:

• Developing and scaling systems for identity verification (IDV), fraud detection, and automated trust/risk reviews that safeguard buyers while minimizing friction for good sellers
• Deliver features across onboarding, education, and seller incentive flows — working across the full stack (backend and frontend)
• Develop seller enrichment pipelines and signals to route sellers to the right onboarding, incentive, and discovery paths
• Design and analyze A/B tests to guide product decisions and accelerate seller success
• Build and maintain data pipelines and growth systems (e.g., notifications, lifecycle triggers) that other pods and teams can leverage

Requirements:

• 3+ Years Of Generalist Software Development Experience In High Growth Startups
• Bachelor's degree in Computer Science, a related field, or equivalent work experience
• Knowledge of multiple programming languages (we primarily use Python, Elixir, JavaScript—knowledge of these in particular not required)
• Web development experience with React, using GraphQL for API development, and modern frontend applications
• Excellent product instincts—you first think about users rather than the best technical solution
• You can mentor others, and prioritize building inclusive, supportive teams
• Project owner—you've strong ownership instincts and can own projects from inception to production and beyond
• You are known for shipping products and features lightning-fast
• You're an excellent problem solver and can operate autonomously
• Ability to pick up on new technologies very quickly
• Proven track record of delivering features
• Exposure to Next.js framework is not required but preferred