Senior Engineering Manager, Clients Team

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 NodeZero™ 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.

You will lead Client Platform — the team responsible for the software that lives in customer environments and makes NodeZero's autonomous pentests possible. Client Platform owns two sub-teams: Image Build & Release (the factory that produces and signs the NodeZero runner container image) and OTA Services (the system that keeps runners current across thousands of customer environments). Every pentest NodeZero runs depends on this team's work being reliable, secure, and fast.

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• Demonstrated expertise leading teams that design, build, and operate containerized software (Docker, VM images) deployed into on-premise or customer-managed environments.

• Experience implementing robust software supply chain practices — secure builds, image signing (cosign, Notary), reproducible builds, and vulnerability scanning in CI.

• Experience designing and operating OTA update mechanisms for distributed agents or edge software at scale — including staged rollouts, rollback, and delivery verification.

• Ability to reason about correctness in opaque, customer-controlled environments where you cannot observe failure modes directly.

• Experience building or significantly growing an engineering team — including hiring, onboarding, and establishing engineering norms tailored for shipped software.

• Proven ability to define and instill engineering culture: rigorous code review standards, robust testing across diverse customer environments, and a strong culture of ownership.

• Drives high-impact architecture decisions rigorously — requires design documents, runs structured reviews, builds consensus, and ensures decisions account for customer environment variables.

• Proficient in Go (preferred), Python, or C++.

• Strong Linux OS-level operations: container runtimes, networking in corporate environments, systemd, process isolation.

• Experience with CI/CD pipelines for building and signing container images (cosign, Notary v2, or equivalent).

• Familiarity with OTA update protocols and frameworks: TUF (The Update Framework), Omaha, or custom mechanisms.

• Understanding of TLS, certificate pinning, and secure software delivery in hostile network environments.

• Exposure to cybersecurity, pentesting tools, or vulnerability remediation.

• Experience with cross-platform agents (Windows/Linux) and endpoint telemetry.

• Background in software running in air-gapped or restricted network environments.

• Familiarity with SLSA supply chain security framework.

We are a fully remote company, and this job may require up to 5% of travel to be successful.

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.

In any materials you submit, you may redact or remove age-identifying information such as age, date of birth, or dates of school attendance or graduation. You will not be penalized for redacting or removing this information.