Principal Security Engineer, Product & AI

As Marqeta’s Principal Security Engineer you will serve as the technical lead across our security engineering function. This role combines three critical responsibilities: leading product security engineering across our payment platform, building our AI security program as we scale generative AI and ML capabilities, and providing security architecture oversight across enterprise and infrastructure security. Your primary focus will be product security and AI—threat modeling payment features, securing APIs, building genAI controls, and ensuring AI-powered capabilities ship securely. You'll also own the security architecture function and provide technical oversight for infrastructure security—endpoint protection, network security, VPN, and enterprise security controls—ensuring coherent security standards across everything we build and operate. You'll partner closely with Product Security, Infrastructure Security, and Security Operations teams and serve as the security voice in our Model Risk Office. This is an individual contributor role with mentoring responsibilities and broad technical influence across the security, engineering, and business technology organizations. We work Flexible First . This role can be performed remotely anywhere within the United States or from our Oakland office. We’d love for you to join us! You'll have the chance to: Lead product security engineering for our payment platform—owning threat modeling, security architecture review, secure SDLC practices, and API security across the engineering organization Help mature our AI security programdeveloping genAI controls, securing ML pipelines, and working alongside the Model Risk Office for model evaluations. Provide security architecture oversight across infrastructure and enterprise security—endpoint, network, VPN, and corporate security controls—ensuring technical standards are coherent across all security domains Shape how security engineering scales across the organization through too