← All roles

Principal Software Engineer, Autonomous Defense

Horizon3 AI· Engineering
Apply on company site
Remote$255k - $300k + equityFull-timePosted 1mo ago

About the role

Senior technical leadership role focused on NodeZero's defensive agents, translating attack paths into continuous actionable remediation, with hands-on coding and architecture work in a multi-tenant, AI-enabled security platform.

Responsibilities

  • Owns the end-to-end technical vision for the workstream and rallies the team around it — from blank doc through shipping, iterating, and deprecating.
  • Production code contributions at Lead/Principle level in a modern backend language (Python, Go, Rust, or similar) in a service-oriented environment.
  • Sets and raises the technical bar (design reviews, code quality, operational discipline) by example rather than by mandate.
  • Mentors and enhances the engineers around them; builds the frameworks and architecture for others to do the best work of their careers.
  • Holds the team accountable to outcomes rather than activity; surfaces risks and tradeoffs early and in writing.
  • Serves as the durable technical interface between AI research and platform engineering, so research direction accounts for platform constraints early rather than at handoff.
  • Translates ambiguous product goals into concrete technical roadmaps.
  • Makes build vs. buy vs. integrate calls with business context, not just engineering preference — including model providers, orchestration frameworks, and control-plane integrations we own versus adopt.
  • Partners closely with PM — comfortable in PRD reviews, not just sprint planning.
  • Sequences an MVP without painting the team into a corner.
  • Designs durable execution for long-running, resumable agent runs.
  • Designs the tool and authorization layer so tenant scope and permissions are enforced by the systems the agent calls.
  • Owns multi-tenant isolation for agents that take write actions.
  • Architects the connector framework over heterogeneous third-party security control APIs.
  • Treats untrusted environment data as an attack surface; understands prompt injection and keeps model output out of the path that authorizes privileged action.
  • Builds observability that makes agent behavior explainable.

Qualifications

  • Bachelor's Degree in Computer Science, Computer Engineering or related field.
  • 10+ yrs professional software engineering experience using modern object-oriented or functional languages (Python, Go, Scala, C++, TypeScript, etc).
  • Experience building applications on cloud computing platforms such as AWS, Azure, GCP, using container technologies such as Docker and Kubernetes.
  • Deep experience with agentic or LLM-backed systems in production with a clear-eyed view of where they fail and how to contain it.
  • Expert proficiency in SQL.
  • Demonstrated experience designing and operating distributed systems in production: asynchronous workflows, queues, retries, idempotency, and partial failure.
  • A track record of shipping and operating production services, including on-call ownership.

Skills

Required:Backend Software EngineeringDistributed SystemsCloud & Containers

Benefits

  • 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.
  • Hybrid & Remote Work: We embrace a mix of remote and hybrid work 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.
Last updated Oct 22, 2026. Interested? Apply on the company site.

About Horizon3 AI

Only Pentesting Platform Proven in Production

Continuously assess, fix, and verify your security posture. Securing enterprises across many attack surfaces.

PentestingSecurity PostureThreat DetectionVulnerabilitiesRisk AssessmentOffensive Security
Company profileWebsite

More open roles at Horizon3 AI