Principal Attack Engineer, AI/LLM

The posting, as Horizon3 wrote it

Get to Know Us

Horizon3 is a fast-growing, remote cybersecurity company dedicated to the mission of enabling organizations to proactively find, fix and verify exploitable attack vectors before criminals exploit them. Our flagship product, the NodeZeroTM platform, delivers production-safe autonomous pentests and other key assessment operations that scale across the largest internal, external, cloud, and hybrid cloud environments. NodeZero has been adopted by organizations of all sizes, from small educational institutions to government agencies and Global 100 enterprises. It is used by IT Ops/SecOps teams, consulting pentesters, and MSSPs and MSPs.

We are a fusion of former U.S. Special Operations cyber operators, startup engineers & operators, and formerly frustrated cybersecurity practitioners. We're committed to helping solve our common security problems: ineffective security tools and false positives, resulting in alert fatigue, blind spots, "checkbox” security culture, cybersecurity skills shortage, and the long lead time and expense of hiring outside consultants. Collectively, we are a team of learn it alls, committed to a culture of respect, collaboration, ownership, and results.

An Overview

We are hiring a Principal Attack Engineer specializing in AI/LLM security to define the long-term technical direction for AI/LLM offense at Horizon3 http://Horizon3.ai. You will lead the company’s most complex and consequential efforts to break AI and agentic systems and turn that research into scalable, autonomous attack capabilities inside NodeZero, our autonomous pentesting platform. This is not consulting or manual pentesting; the goal is to establish durable, production-grade capabilities that materially expand how NodeZero finds and validates exploitable attack paths across customer environments. The focus is LLM-based applications: the chatbots, copilots, RAG pipelines, and AI agents that enterprises expose to employees, customers, and the internet.

You will operate at the intersection of company strategy and technical direction. You will shape the vision for AI/LLM offensive capabilities, partner with senior leadership on major technical and product decisions, and create the architecture, standards, and organizational alignment required for multiple teams to execute against that vision. This is a rare, company-wide role for a technical authority whose judgment influences the business and, where appropriate, the broader AI security field.

What You’ll Do

Company-wide Technical Leadership & Scope

• Define the long-term technical vision for AI/LLM offense and its role in NodeZero and the company’s broader product strategy.
• Partner with senior engineering, product, and business leadership to shape priorities, investment decisions, risk posture, and the roadmap for AI/LLM offensive capabilities.
• Set direction for the most complex, high-risk, and business-critical AI/LLM programs; establish the outcomes and decision principles

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models depending on role and location, including our Chicago office, where some roles require regular in-office presence.

• Competitive Compensation: We offer competitive salary, equity and benefits. Our benefits include health, vision & dental insurance for you and your family, a flexible vacation policy, and generous parental leave.

You Belong Here

Horizon3 is not just an equal opportunity employer - we are a community that values diversity, equity, and inclusion as fundamental principles of our culture and success. We are dedicated to fostering a workplace where everyone feels welcome and respected, regardless of race, color, religion, sex, national origin, age, disability, veteran status, sexual orientation, gender identity or expression, genetic information, marital status, hair length or any other legally protected status by law.

Our commitment to diversity and inclusion means we strive to attract, develop, and retain a workforce that reflects the varied communities we serve. We believe that diverse perspectives drive innovation and strengthen our ability to create cutting-edge cybersecurity solutions. At Horizon3, every team member is valued and supported in an environment that encourages personal and professional growth.

We welcome candidates from all backgrounds and experiences, and we encourage all qualified individuals to apply. Come be a part of Horizon3, where your unique contributions are recognized, and your potential is limitless.

Other Duties

Please note this job description is not designed to cover or contain a comprehensive listing of activities, duties or responsibilities that are required of the employee. Duties, responsibilities, and activities may change at any time with or without notice.

Application Note

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