Head of Security

About Lightfield

Lightfield is reimagining CRM as a world model of a business. By learning from emails, meetings, and customer conversations, we’re building a living understanding of how a company works—so AI can help teams anticipate what comes next, make better decisions, and take action.

More than 5,000 companies have used the product since its November launch. We’ve raised more than $70M from Andreessen Horowitz, Coatue, Maverick Ventures, and Greylock to attack the biggest software category in the world. We previously built Tome, which reached more than 25 million users, and our team brings experience from Llama, Instagram, Google, and Salesforce.

About the role

We’re looking for an experienced, deeply technical security leader to build and lead security at Lightfield.

Security is fundamental to the product we’re building. Lightfield connects to some of a company’s most sensitive systems and data, including email, calendars, meetings, Slack, and CRM data, and uses that context to power AI agents that can take action on a company’s behalf.

You’ll own how we protect that data and build systems our customers can trust. Your scope will span product and infrastructure security, AI and agent security, identity and access, incident response, compliance, and customer security.

This is a hands-on role. You’ll work directly in the systems you’re responsible for: reviewing architecture and code, threat modeling new products, investigating vulnerabilities and incidents, implementing security controls, and improving our infrastructure. You’ll set the security strategy, but you’ll also do much of the work to execute it.

As the company grows, you’ll build the security team around you. We’re looking for someone who has already led a security function and is excited to get close to the technology again and build the next one from the ground up.

You’ll report to the CTO and have significant ownership and visibility across the company.

What you’ll do

• Own Lightfield’s security strategy and roadmap, identifying the risks that matter most and driving them to resolution.
• Partner with engineers on product and infrastructure security, including architecture reviews, threat modeling, code review, vulnerability remediation, and implementation of security controls.
• Define and evolve the security model for AI agents, including permissions, tool access, sandboxing, data boundaries, and safe execution.
• Build and operate the systems that underpin our security program, including identity and access, vulnerability management, detection and monitoring, incident response, and data protection.
• Lead the response to security incidents and personally dig into the systems, logs, and code needed to understand and resolve them.
• Own our security and compliance program, including SOC 2 and the requirements that come with moving further into the enterprise.
• Work directly with customers and prospects on security reviews, architecture discussions, and complex security requirements.
• Build security into how we operate through good architecture, tooling, and collaboration rather than unnecessary process.
• Build and lead the security team as our needs grow.

What we’re looking for

• You’ve previously led the security function at a high-growth technology company, with end-to-end responsibility for security.
• You’ve built a security program through a meaningful stage of company growth. You know what to do first, what can wait, and how the function needs to evolve as the company scales.
• You’re a deeply technical security leader who is equally comfortable working in code and infrastructure, setting security strategy, and engaging with executives and customers.
• You have strong application and cloud security expertise and can reason about attack surfaces, trust boundaries, and failure modes.
• You’ve owned security and compliance programs such as SOC 2 and worked directly with enterprise customers and their security teams.
• You have exceptional judgment. You can distinguish material risks from theoretical ones and improve security without unnecessarily slowing the company down.
• You know how to build a security organization: what to own centrally, what to embed in engineering, when to use vendors, and when and whom to hire.
• You’re excited to develop security models for AI agents and other emerging systems where established patterns are still evolving.