Attack Engineer

Get to Know Us

Horizon3.ai 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.

As a remote first company, we require minimum 25Mbps consumer grade broadband connection.

Summary

• We’re seeking an experienced Attack Engineer who blends deep software engineering expertise with a passion for cybersecurity. In this role, you’ll design and build production-grade systems that drive the offensive capabilities of the NodeZero platform. You’ll be responsible for researching and weaponizing real-world vulnerabilities and misconfigurations, and leveraging AI technologies to automate and enhance attack workflows.

• Ideal candidates are fluent in Python, comfortable shipping robust code to production, and excited by the challenge of applying their engineering skills to offensive tooling, and autonomous/agentic orchestration. This is a high-impact, cross-disciplinary role for someone who wants to shape the future of autonomous offensive security.

Essential Functions

• Research and develop novel attack capabilities for integration into the NodeZero platform, focusing on autonomous red teaming, offensive security automation, and external perimeter breach techniques.

• Acquire, configure, and exploit vulnerable test environments to validate and demonstrate attack scenarios.

• Extend and maintain platform architecture and data models to support new research and product features.

• Monitor public vulnerability databases and threat intelligence sources to stay current on emerging threats.

• Collaborate cross-functionally with engineers, product managers, and customer teams to resolve issues, enhance features, and drive customer value.

• Mentor teammates and improve team processes, code quality, and research standards.

• Author technical blog posts and internal documentation showcasing new capabilities, research, and methodologies.

Competencies / Requirements

Software Engineering

• 7+ years of combined experience in software engineering and red teaming/ offensive security.

• Expert-level proficiency in Python for large-scale development.

• Proficient in object-oriented design, test-driven development, and scalable code design.

• Experience designing and integrating APIs, data structures, and full-stack system components.

• Experience developing in fast-paced, product-driven environments with distributed teams.

• Skilled with Git and modern team collaboration workflows (PRs, CI/CD, code reviews).

• Familiar with containerization and orchestration tools such as Docker and Kubernetes.

• Comfortable working with relational (Postgres) and graph (Neo4j) databases.

Offensive Security

• Hands-on experience with developing tools for offensive cybersecurity and/or red team operations.

• Deep understanding of common RCE techniques (e.g., SQL injection, buffer overflows, path traversal).

• Familiar with exploitation of network protocols, web applications, and complex enterprise software.

• Ability to translate security research into functional, autonomous attacks within a product context.

• Experience attacking Windows environments (e.g., Active Directory), cloud platforms (AWS, Azure, GCP), and/or Kubernetes.

Desired Skills

• Bachelor's degree in Computer Science or a related field.

• OSCP (Offensive Security Certified Professional) or equivalent certifications.

• Demonstrated experience using AI or LLM-based tools to enhance or automate exploit development, vulnerability triage, or security research workflows.

• Contributions to open-source security tools, technical blog posts, or public vulnerability research.

• Prior development experience within large-scale or multi-tenant SaaS applications.

• Familiarity with Nuclei, Metasploit, BloodHound, and similar offensive tooling.

Expectations

• Outstanding analytical and problem-solving aptitude, especially when dealing with unfamiliar systems.

• Self-motivated and energetic with the ability to operate independently with minimal supervision.

• Ability to manage multiple priorities and deliver on both short- and long-term objectives.

• Strong written and verbal communication skills; capable of creating technical documentation and explaining complex topics to a broad audience.

• Demonstrated curiosity and adaptability; quick to adopt new technologies and domains.

Travel Required

We are a fully remote company, and this job may require up to 5% 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. Our compensation structure is designed to be fair, competitive, and transparent, ensuring that every team member is recognized and compensated equitably across roles, levels, and locations.

In accordance with various State’s transparency regulations, we provide the following salary range information for this position:

• Base salary range (based on level):

  • P3, Tier 1–2: $181,000 – $223,000

  • P4, Tier 1–2: $196,000 – $242,000

  • This position may be filled at either the P3 or P4 level depending on experience, skills, and interview performance. Final compensation is further determined by Tier 1 vs. Tier 2 location alignment.

• Additional compensation: All full-time roles are eligible for an equity package in the form of stock options.

Perks of Horizon3.ai

• Inclusive Team: We value diversity and promote an inclusive culture where everyone can thrive.

• Growth Opportunities: Be part of a dynamic and growing team with numerous career development opportunities.

• Innovative Culture: Work in a collaborative environment that encourages creativity and out-of-the-box thinking.

• Remote Work: We are a 100% remote company. Enjoy the flexibility to work in the way that supports you and brings out your best.

• 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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