Sr. Staff AI Security Engineer

BILL is a financial automation company that helps businesses streamline and control their operations. The Sr. Staff AI Security Engineer will lead the secure deployment and operation of AI and ML systems, designing security infrastructure, conducting adversarial research, and embedding security into the AI development lifecycle. The role also owns the AI security roadmap, advises senior leadership, and mentors engineers.

Responsibilities:

• Design, build, and operate secure AI gateways and policy orchestration layers spanning multiple AI models and service providers
• Configure end point settings for AI tools in collaboration with IT end point management solutions
• Stand up and lead a formal AI red-teaming practice covering prompt injection, jailbreaking, model extraction, and emerging attack vectors
• Identify and mitigate AI-specific threats across input manipulation, supply chain (model weights, datasets, third-party AI libraries), data privacy (training data leakage, PII disclosure), and model integrity (poisoning, unauthorized fine-tuning)
• Automate security checks and guardrails to enable rapid development cycles without sacrificing security posture
• Apply and operationalize the OWASP LLM Top 10 framework to categorize and mitigate risk
• Own the AI security roadmap and advise senior leadership on AI risks and safe adoption
• Embed with platform teams as a partner, fostering a collaborative security culture
• Mentor fellow engineers on AI security best practices
• Document and report vulnerabilities with clear remediation guidance and technical direction

Requirements:

• A proven track record of building and scaling security systems in high-growth environments
• High proficiency in Python or Go to build, automate, and scale security tooling
• Deep understanding of LLM-specific attack vectors: prompt injection and jailbreaking
• Deep understanding and applied experience with the OWASP LLM Top 10 framework
• Experience designing secure API gateways, orchestration layers, and scalable security infrastructure using infrastructure as code
• Experience standing up red-teaming or adversarial testing programs
• A strong grasp of AI/ML fundamentals, including model supply chain and data privacy risks
• A builder mentality and passion for the AI space—you enable development through secure architecture rather than blocking it
• The ability to influence senior leadership and mentor engineers across the organization
• A background in Computer Science, Cybersecurity, or a related technical field
• Applicants must have authorization to work in the United States without requiring visa sponsorship now or in the future