Senior Offensive Engineer - Autonomous Internal Attacks

Horizon3; Oregon; Hybrid; USD 206,000 - 243,000; Full time

Benefits offered by this job

Health, vision & dental insurance

Equity package

Flexible vacation policy

Parental leave

Job summary

Horizon3 is a fast-growing cybersecurity company delivering the NodeZero autonomous pentesting platform for large, hybrid environments. We seek a Senior Attack Engineer to lead complex internal network and Active Directory attack projects and to weaponize real-world vulnerabilities into safe, scalable product capabilities.

You will design production-grade Python systems, own end-to-end attack capabilities, mentor teammates, and collaborate with engineers and customer-facing teams to deliver

Qualifications

• Deep, hands-on offensive security experience against internal enterprise networks and Active Directory, from foothold through enterprise compromise.
• Expert-level proficiency in Python for large-scale development and production-quality code.
• Strong command of internal network attack techniques, including network protocol exploitation, privilege escalation, lateral movement, and credential access.
• Experience with object-oriented design, API integration, data structures, and building scalable system components in fast-paced product environments.
• Experience designing complex software components or systems with focus on extensibility, safety, performance, and long-term maintenance.
• A track record of independently leading complex, high-impact technical projects with risk awareness and business implications.
• Strong written and verbal communication, including clear technical documentation and stakeholder communication.
• Mentorship and efforts to improve team processes, tooling, or standards.
• Offensive security and software engineering background aimed at turning research into safe product capabilities.

Responsibilities

• Research and develop novel attack capabilities for integration into the NodeZero platform as autonomous red-team content.
• Research and translate emerging tradecraft into production attack content for internal networks and AD.
• Design, build, and maintain production-grade Python systems balancing attack effectiveness with safety and reliability.
• Acquire, configure, and exploit modern, hardened test environments to validate attack scenarios.
• Monitor vulnerability databases and threat intelligence to update attack modules.
• Extend platform architecture and graph models for new identity and privilege paths.
• Shape coverage priorities using customer needs and threat intel; scope projects and raise risks.
• Mentor teammates, improve code quality, and reinforce research safety practices.
• Collaborate cross-functionally to resolve issues, enhance features, and produce technical docs.

Skills

Offensive security

Python development

Network attack techniques

OO design

System design

Technical leadership

Technical communication

Mentorship

Autonomous tooling

Tools

BloodHound

Impacket

Docker

Kubernetes

Neo4j

Job description

Horizon3 is a fast-growing cybersecurity company delivering the NodeZero autonomous pentesting platform for large, hybrid environments. We seek a Senior Attack Engineer to lead complex internal network and Active Directory attack projects and to weaponize real-world vulnerabilities into safe, scalable product capabilities.

You will design production-grade Python systems, own end-to-end attack capabilities, mentor teammates, and collaborate with engineers and customer-facing teams to deliver