Software Engineer, Fraud

Whatnot•San Francisco, CA

63d•$180•Hybrid

About The Position

Whatnot is the largest live shopping platform in North America and Europe to buy, sell, and discover the things you love. We're re-defining e-commerce by blending community, shopping, and entertainment into a community just for you. As a remote co-located team, we're inspired by innovation and anchored in our values. With hubs in the US, UK, Germany, Ireland, and Poland, we're building the future of online marketplaces -together. From fashion, beauty, and electronics to collectibles like trading cards, comic books, and even live plants, our live auctions have something for everyone. And we're just getting started! As one of the fastest growing marketplaces, we're looking for bold, forward-thinking problem solvers across all functional areas. Check out the latest Whatnot updates on our news and engineering blogs and join us as we enable anyone to turn their passion into a business, and bring people together through commerce. Role The Trust and Risk, Fraud, and Integrity teams at Whatnot are responsible for building systems that help set clear expectations, encourage good behavior, and address issues fairly and efficiently. By combining proactive detection with transparent enforcement, we ensure Whatnot remains a safe and trustworthy place for both buyers and sellers.. We focus on: Policy enforcement and dispute resolution: Designing systems that set clear behavioral expectations, detect and address policy violations, and resolve disputes efficiently. Reusable, high-performance platforms: Building and maintaining scalable infrastructure that powers internal operations, automated and manual actioning systems, and advanced detection capabilities. Intelligent detection and prevention: Leveraging machine learning, behavioral analysis, and real-time interventions to stay ahead of evolving abuse patterns and protect both buyers and sellers. Continuous improvement: Using feedback loops and monitoring systems as managed assets for ongoing quality assurance and for strengthening algorithms, methodologies, and operational processes. Together, these teams ensure Whatnot remains a trusted, safe, and thriving marketplace for all users. US Based: Team members in this role are required to be within commuting distance of our Los Angeles, San Francisco, New York, and Seattle hubs.

Requirements

7+ years of total software engineering experience
Bachelor's degree in Computer Science, Statistics, Applied Mathematics, Economics, a related technical field, or equivalent work experience.
4+ years of software engineering experience building for consumer-scale loads.
1+ years of experience writing production code in Python.
Business intuition & a data-driven mindset that enables you to think critically about the growth headwinds abuse prevention systems can create.
Obsession with impact. You are focused on driving value for users & have a track record of deploying simple solutions wherever feasible. You move as fast as possible without sacrificing quality.
Relentnessness & entrepreneurship. You prioritize your work ruthlessly & run through walls to get things done. Your curiosity drives you to dig into user problems & craft suggestions on how we can address them.
Ability to work autonomously and lead initiatives across multiple product areas and communicate findings with leadership and product teams.
Comfortability with data warehouses and transformation tools such as Snowflake, dbt, Dagster.
Professionalism around collaborating in a remote working environment and well tested reproducible work.
Above average documentation and communication skills.

Nice To Haves

1+ years of experience in Trust and Risk or Integrity or Fraud domains preferred.
Explicit data science or machine-learning experience is a huge plus.

Responsibilities

Design and develop systems to protect the platform: Build and iterate on production algorithms and infrastructures that mitigate systemic risks and safeguard buyers, sellers, and the broader Whatnot community.
Balance risk and user experience: Proactively monitor the impact of protective systems on trusted users, ensuring interventions deliver more value than friction.
Respond in real time to threats: Architect event-driven pipelines and detection frameworks that enable near real-time responses to high-risk user behavior.
Contribute across the full development lifecycle: Engage in ideation, scoping, prototyping, load testing, deployment, and monitoring to deliver resilient and scalable solutions.
Drive cross-team initiatives: Collaborate across multiple product surfaces and operational teams, surfacing insights to leadership and stakeholders through dashboards, notebooks, and clear written documentation.
Continuously evolve defenses: Stay ahead of emerging abuse patterns, abuse vectors, and account integrity risks by iterating quickly and rigorously testing solutions.

Benefits

Generous Holiday and Time off Policy
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
All Whatnauts are expected to develop a deep understanding of our product. We're passionate about building the best user experience, and all employees are expected to use Whatnot as both a buyer and a seller as part of their job (our dogfooding budget makes this fun and easy!).
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.