Machine Learning Engineer - Applied AI

Get to Know Us

Horizon3.ai is a fast-growing, remote cybersecurity company dedicated to the mission of enabling organizations to proactively find and 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 ITOps/SecOps teams, consulting pentesters, and MSSPs and MSPs. 

We are a fusion of former U.S. Special Operations cyber operators, startup engineers, and formerly frustrated cybersecurity practitioners. We're committed to helping solve our common security problems: ineffective security tools, 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.

What We're Looking For:

We're looking for an Machine Learning Engineer - Applied AI with deep experience deploying emerging AI technology in production and a demonstrated interest in security. You will have a major impact in how we add value to our customers by using emerging AI technologies and exposing their vulnerabilities. You will help design and implement AI solutions—from crafting components for offensive security operations to contributing to our autonomous offensive testing capabilities—that surface vulnerabilities across the AI application stack and outputs, partnering closely with senior engineers to translate research into reliable, scalable systems. This position requires practical expertise in creating, implementing, launching, machine learning systems and an interest in attacking them.

Essential Functions

• Build sophisticated AI systems capable of discovering vulnerabilities and streamlining penetration testing methodologies

• Research and implement AI-driven vulnerability detection and exploitation methods

• Automate exploitation workflows using AI technologies

• Lead complete development lifecycles for AI features from concept through deployment

• Design and implement advanced testing capabilities that detect vulnerabilities in AI-native applications

• Research and target emerging attack vectors specific to applications developed with AI and implement detection methods

• Implement scalable solutions that can use AI to exploit traditional CVEs, credential-based attack paths, and data pilfering vectors

• Guide technical conversations, assess code quality, and facilitate design meetings while sharing knowledge to enhance team capabilities

• Support and guide less experienced team members, fostering their professional development

Competencies/Requirements

• 3+ years proven track record building and deploying AI/ML solutions in live environments

• Expert-level Python programming abilities

• You’ve shipped and maintained AI/ML systems, not just built prototypes, and ideally in multiple domains

• Demonstrated interest in cybersecurity and penetration testing

• Knowledge of AI frameworks and machine learning libraries (such as TensorFlow, PyTorch, Hugging Face, OpenAI APIs, and LangChain)

• Experience with ML data preprocessing techniques including normalization, feature engineering, and dataset preparation for model training and fine tuning

• Experience with cloud AI platforms such as AWS Bedrock, AWS SageMaker, and Azure AI, with ability to implement and optimize solutions across environments

• Strong analytical skills and ability to clearly communicate complex security concepts

• Comprehensive understanding of various database technologies, including relational and non-relational systems

Desired/Nice to Have

We don’t expect these, but they elevate your application to “unicorn” status.

• Background in training specialized machine learning models for security purposes

• Experience with and understanding of AI-specific vulnerabilities

• Background in AI security offense, testing AI system vulnerabilities, or creating automated security solutions powered by artificial intelligence

• Previous experience analyzing security using large language models, conducting penetration testing

• Experience with AI red teaming or learning model vulnerabilities

• Demonstrated examples of exploiting AI-specific vulnerabilities

• Background in AI security offense, testing AI system vulnerabilities, or creating automated security solutions powered by artificial intelligence

• Previous experience analyzing security using large language models, conducting penetration testing enhanced by AI technologies, and researching machine learning weaknesses and countermeasures

Expectations:

• Outstanding problem-solving aptitude, a “hacker mindset”.

• Be self-motivated and highly energetic to have the ability to operate effectively with limited supervision and guidance.

• Strong technical documentation and communication skills.

• Ability to manage concurrent initiatives and use effective judgment in prioritization and time management.

• Excellent analytical/problem solving ability.

What makes you stand out:

Elevate your application to “unicorn” status:

• Experience identifying attack paths across full-stack environments

• Background in application security testing, penetration testing, or offensive security

• Understanding of web application security fundamentals

• Certification(s) demonstrating cybersecurity expertise such as OSCP, CISSP, GPEN, Security+, LPT, or CEH.

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 convenience and work-life balance that comes with remote work. 

• 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.

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.

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

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, 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.