Senior Staff AI Security Engineer
About this role
Protecting advanced financial automation tools from emerging threats requires securing the underlying artificial intelligence and machine learning systems against unique vulnerabilities. As a Senior Staff AI Security Engineer at BILL, you will establish the defensive foundation that enables developers to build and scale production systems safely. Your primary mission involves designing secure gateways, orchestration layers, and adversarial testing practices that address risks like prompt injection, model poisoning, and data leakage without slowing down engineering velocity.
You will operate as an enabler and technical partner rather than a traditional gatekeeper, embedding security directly into the development lifecycle across platform, engineering, and IT teams. Ideal candidates combine deep technical fluency in Python or Go with a strong background in AI security frameworks, strategic leadership experience, and a builder mentality. Success in this role means shaping the long-term security roadmap while mentoring engineers and advising senior leadership on complex AI risks.
What you will do
- Design, build, and operate secure AI gateways and policy orchestration layers spanning multiple AI models and service providers.
- 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 components, data privacy, and model integrity.
- 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 while mentoring fellow engineers on AI security best practices.
What you need
- Demonstrate a proven track record of building and scaling security systems in high-growth environments.
- Possess high proficiency in Python or Go to build, automate, and scale security tooling.
- Showcase a deep understanding of LLM-specific attack vectors including prompt injection and jailbreaking.
- Bring deep understanding and applied experience with the OWASP LLM Top 10 framework.
- Have experience designing secure API gateways, orchestration layers, and scalable security infrastructure using infrastructure as code.
- Hold experience standing up red-teaming or adversarial testing programs.
- Maintain a strong grasp of AI/ML fundamentals, including model supply chain and data privacy risks.
- Possess a background in Computer Science, Cybersecurity, or a related technical field.
Benefits
- Medical, dental, and vision plans
- HSA & FSA accounts
- Life Insurance, Long & Short-term disability coverage
- Employee Assistance Program
- Paid holidays, wellness days, and flexible time off
- Employee Stock Purchase Program and 401(k) retirement plan
Skills and tech stack
Questions candidates ask
What is the remote work policy?
The company is remote-first, with office spaces in San Jose, California and Draper, Utah, and opportunities to connect in person when it counts.
What is the salary range for this position?
The estimated salary range for the San Jose location is $194,300 to $243,000 USD, while the range for the Draper, UT location is $165,200 to $206,600 USD.
What technical skills are required for the role?
Applicants need high proficiency in Python or Go, a deep understanding of LLM-specific attack vectors, and applied experience with the OWASP LLM Top 10 framework.
Is visa sponsorship available?
This position is not eligible for visa sponsorship, and applicants must have authorization to work in the United States without requiring sponsorship.