Senior Application Security Engineer

Brex is an AI-powered spend management platform providing integrated corporate cards, banking, global payments, and expense software to startups and enterprises worldwide. The Senior Application Security Engineer identifies and mitigates security vulnerabilities across Brex’s platform. This role performs penetration testing, security reviews, and AI feature security assessments while building tooling and driving secure development practices across engineering teams.

Brex is seeking a Senior Application Security Engineer to strengthen the security posture of its AI-powered financial platform. This role focuses on identifying vulnerabilities, demonstrating business impact, and embedding secure development practices across engineering teams. Working within the broader Financial Scale organization, the engineer will collaborate with Product Security, Security Operations, GRC, and Infrastructure teams to protect complex distributed systems and emerging AI-driven features.

Responsibilities:
- Identify vulnerabilities across the platform, demonstrate exploit impact, and articulate risk for prioritization.
- Perform penetration testing and security design reviews to identify insecure implementations.
- Develop and maintain tooling for static and dynamic application security testing (SAST/DAST).
- Support secure development workflows through automation and developer education.
- Partner with product and engineering teams to secure AI-powered and agentic features.
- Contribute to a culture of security excellence through mentorship and technical leadership.

Requirements:
- 5+ years of experience in application security or related roles.
- Proven ability to discover vulnerabilities in complex systems and craft exploit chains.
- Experience with threat modeling, incident response, and secure development practices.
- Proficiency in Python or scripting languages and familiarity with AI workflows.
- Strong communication skills and collaborative mindset.
- Experience securing distributed cloud systems preferred.

Benefits:
- Competitive salary range of 192,000–240,000 USD plus potential equity.
- Opportunity to influence AI security strategy within a leading fintech platform.
- Collaborative engineering culture with high autonomy.
- Career growth within a rapidly scaling global organization.

This full-time remote role requires deep technical expertise in application security and a proactive approach to securing AI-driven financial systems.