[Hiring] Principal Attack Engineer @Horizon3

Role Description

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. 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.

What You’ll Do

• 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 against which teams execute.
• Lead cross-company initiatives that require alignment across Attack Engineering, Platform, Product, customer-facing teams, and other technical functions.
• Diagnose systemic blockers in architecture, process, operating model, or technical capability and drive durable resolution.
• Define company-wide standards for reliability, safety, observability, evaluation, testing, cost management, and operational readiness in LLM-powered offensive systems.
• Develop P5 engineers and other senior technical leaders, multiplying the organization’s capacity to reason about and deliver AI/LLM security capabilities.
• Communicate clearly with executives, technical leaders, and external stakeholders; bring the organization through major technical transitions with clarity and composure.

Attacking AI/LLM Systems

• Own NodeZero's coverage strategy for the OWASP Top 10 for LLM Applications.
• Set the company’s research and productization agenda for breaking AI and agentic systems.
• Identify novel, high-leverage attack classes and establish the frameworks, abstractions, and coverage models needed to make them repeatable in NodeZero.
• Direct the company’s approach to various agentic attack paths.
• Set technical direction for assessing AI infrastructure.
• Evaluate the strategic significance of model and supply-chain attacks.
• Establish a durable threat-modeling approach for agentic systems.
• Ensure research becomes safe, reliable, scalable product capability.
• Serve as the definitive internal technical authority on the hardest and most novel AI/LLM offensive problems.

Building with LLMs

• Set the long-term architecture for LLM-powered offensive applications.
• Establish company-wide principles for cost, safety, and reliability.
• Guide the architecture of microservices and shared platforms.
• Lead architectural transformations when necessary.
• Ensure the organization can operate and improve these systems over time.

Qualifications

• Exceptional Python and software engineering expertise.
• Deep expertise in offensive security, penetration testing, exploit development, or a closely related discipline.
• Recognized expertise in AI/LLM and agentic-system security.
• Deep command of the OWASP Top 10 for LLM Applications and MITRE ATLAS.
• A track record of shipping or shaping high-impact security capabilities.
• Demonstrated ability to define long-term technical vision and resolve ambiguous problems.
• Company-wide technical judgment.
• Proven ability to develop senior technical talent.
• Self-motivated and deeply engaged with the direction of the AI security industry.

What Sets You Apart

• Experience setting technical direction across an engineering organization.
• Industry-level contributions to AI security research.
• Experience shaping strategy for cloud AI platforms.
• Deep experience with agentic architectures and AI infrastructure security.
• Background in traditional exploit development or building offensive security platforms.
• CTF experience, particularly in AI/ML-focused challenge categories.
• A record of strengthening a company’s technical credibility.

Travel Required

We are a fully remote company, and this job may require up to 10% of travel to be successful.

Compensation and Values

At Horizon3, we believe that our people are our greatest asset, and our compensation philosophy reflects this core value. We are committed to fostering an environment where all employees feel valued, respected, and rewarded for their contributions.

• Base salary range: $238,000 - $280,000.
• Additional compensation: All full-time roles are eligible for an equity package in the form of stock options.

Perks of Horizon3

• Inclusive Team: We value diversity and promote an inclusive culture.
• Growth Opportunities: Be part of a dynamic and growing team.
• Innovative Culture: Work in a collaborative environment.
• Hybrid & Remote Work: We embrace a mix of remote and hybrid work models.
• Competitive Compensation: We offer competitive salary, equity, and benefits.

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.

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.

Application Note

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