Head of Security

About Exa

Exa is an applied AI lab building a search engine unlike the world has ever seen. We build massive-scale infra to crawl the entire web, train state-of-the-art embedding models to process it, and design super high performant vector databases to retrieve over it. We now power search for Cursor, Cognition, HubSpot, and over 400,000 developers and have raised $350m from Lightspeed, Benchmark, and a16z.

What You’ll Own

• Define Exa’s company-wide security strategy, operating model, risk framework, and multiyear roadmap.
• Establish Exa’s security posture and risk appetite in partnership with the founders and executive team.
• Provide leadership with clear, decision-ready assessments of material risks, incidents, investments, and tradeoffs.
• Own security architecture and engineering across Exa’s products, APIs, web-scale data pipelines, cloud environments, Kubernetes clusters, model-training systems, GPU infrastructure, and internal platforms.
• Protect customer data, proprietary models, training data, source code, credentials, and other high-value assets from external attacks, insider threats, supply-chain compromise, and misuse.
• Build security into the product-development lifecycle through threat modeling, architecture reviews, secure defaults, automated controls, vulnerability management, offensive testing, and engineering education.
• Establish identity, access, secrets, key, certificate, and service-trust systems across human users, workloads, training jobs, and AI agents.
• Build Exa’s detection, investigation, incident response, crisis management, and recovery capabilities; serve as the accountable leader during significant security incidents.
• Own corporate security, including endpoints, SaaS applications, employee access, security awareness, insider risk, physical-security interfaces, and third-party risk.
• Lead security governance, regulatory readiness, compliance, and customer assurance, including programs such as SOC 2 and ISO 27001.
• Represent Exa’s security program in strategic customer conversations, enterprise reviews, audits, and other high-trust settings.
• Define the security organization’s structure, budget, technology strategy, external partnerships, and hiring plan.
• Recruit, develop, and lead an exceptional security team while creating a culture in which every team shares responsibility for security.
• Establish meaningful security metrics and regularly communicate Exa’s posture, priorities, and progress to company leadership.

What We’re Looking For

• You have built or led security at a technically ambitious, rapidly growing infrastructure, AI, developer-platform, cloud, or enterprise-software company.
• You have operated with company-wide accountability for security—not merely responsibility for an individual security discipline.
• You combine executive judgment with deep technical credibility. You can move comfortably between company strategy, business risk, system architecture, incident investigation, and implementation details.
• You approach unfamiliar problems with the mindset of both a builder and an attacker, and you are energized by security challenges for which no established playbook exists.

This is an in-person opportunity in San Francisco. We’re happy to sponsor international candidates (e.g., STEM OPT, OPT, H1B, O1, E3). In addition to premium healthcare benefits (medical, dental, vision), we also offer fertility benefits and a monthly wellness stipend to all of our employees.