Responsibilities
- Perform security-focused code reviews and recommend practical fixes for identified vulnerabilities.
- Partner with product and engineering teams on threat modeling and application security reviews.
- Investigate, reproduce, triage, and help remediate vulnerabilities in web and mobile applications.
- Support the bug bounty program by investigating reports and coordinating remediation.
- Support preparation of security releases.
- Develop reusable security patterns, processes, and automated tooling to prevent security issues.
Requirements
- At least five years of relevant experience.
- Software development experience in one or more of Python, Elixir, or JavaScript.
- Ability to identify security vulnerabilities through code review and work with engineers on effective fixes.
- Understanding of application security risks, threat modeling, and security reviews.
- Ability to investigate, reproduce, and triage web and mobile application vulnerabilities.
- Strong communication and collaboration skills for explaining security risks and recommendations.
- Practical problem-solving approach and interest in building reusable security tools and processes.
Benefits
- Flexibility to work from home or from one of Whatnot’s global office hubs.
- Team members must live within commuting distance of the Krakow hub.
- The company values in-person time for planning, problem-solving, and connection.
Tech Stack
Categories
About Whatnot
Whatnot is the largest livestream shopping platform in the US, UK, and Europe. Millions of people come to Whatnot every day to buy, sell, and connect over the things they love, from sneakers to sports cards, vintage fashion to fine jewelry, comics to Pokémon, beauty, electronics, and hundreds of other categories. In 2025, live sales on Whatnot surpassed $8B, more than doubling the year before. Over 20 million accounts were created last year alone, and we have been the #1 shopping app in both the US and UK. We've built a real business, but we're nowhere near done. Live commerce at this scale has never been done in the West, which means the people here now are shaping how an entirely new industry develops. The pace here is fast and the expectations are high. We move quickly, prioritize ruthlessly, and trust people to own their work end-to-end. In return, careers grow faster, impact is real, and your colleagues will raise your standards. It's an environment built for people who want to do the best work of their careers alongside others doing the same. We're a remote, co-located team with hubs in the US, UK, Ireland, Poland, and Germany, and we're hiring across every function.