Staff Application Security Engineer

This position is listed on behalf of a partner company, who manages all applications and next steps. Our partner is looking for a Staff Application Security Engineer based in United States.

Help establish and scale a dedicated application security function within a high-growth technology environment where protecting customers against fraud and abuse is a core priority. As a senior individual contributor, you will combine deep security expertise with hands-on software engineering to identify vulnerabilities, strengthen development workflows, and build practical security tooling. You will design secure software development practices, lead threat modeling and security reviews, and drive vulnerability remediation across complex APIs, SDKs, and cloud-based systems. Working closely with engineering teams and security leadership, you will integrate AI-powered tools into security testing and remediation while maintaining rigorous quality standards. This role offers substantial technical autonomy, opportunities to influence engineering practices across the organization, and the chance to solve challenging security problems at scale. You will help make security an integral part of product development rather than a separate compliance requirement.