About the Job
Horizon3 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...
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" sec...
As a remote first company, we require minimum 25Mbps consumer grade broadband connection.
Key Responsibilities
The Expert Engineer on the OTA Services team is the technical anchor for how NodeZero updates itself across thousands of customer deployments — without customer intervention, without downtime, and without introducing new vulnerabilities in the process. NodeZero runs as a container inside customer infrastructure. When a new image is ready, the OTA system has to find every deployed instance, negotiate the update, deliver it safely, validate it, and roll back gracefully if something goes wrong. Getting that right at scale, across diverse customer environments including air-gapped and restricted networks, is a genuinely hard systems problem.
This is a hands-on staff-level role. You will write production code, produce architecture designs, set the technical direction for update delivery and version management, and mentor P4 engineers on the team. The OTA Services team works in close partnership with the Image Build & Release team — your counterpart on the build side produces the artifacts you deliver. This role reports to the Client Platform Engineering Manager.
OTA Architecture: Design and own the over-the-air update system — the delivery protocol, version negotiation, rollout orchestration, health verification, and automatic rollback
Deployment Fleet Management: Own the systems that track the version state of every NodeZero deployment — know what's running where, what's pending, and what's stuck
Rollout Strategy: Design safe rollout strategies for updates — phased rollouts, canary deployments, customer pinning, and emergency hold mechanisms
Constrained Environment Delivery: Design delivery mechanisms that work reliably across diverse customer environments including air-gapped networks, strict egress policies, and minimal-footprint deployments
Reliability & Incident Response: Own OTA system reliability end-to-end — on-call for delivery failures, stuck updates, and version drift incidents
Mentorship: Mentor P4 engineers through design review, code review, and technical pairing; be the person the team turns to when delivery semantics get complicated
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.
Required Skills & Abilities
8+ years of professional software engineering experience with deep specialization in distributed systems, remote update systems, or fleet management infrastructure
Deep understanding of remote update system design — delivery protocols, version negotiation, delta delivery, health verification, and rollback semantics
Experience designing rollout strategies for software deployed across heterogeneous, customer-managed environments — you understand the difference between a lab rollout and rolling something out to thousands of production deployments you don't control
Strong proficiency in Go, Python, or Rust for systems-level infrastructure work
Experience building software that operates in constrained or air-gapped environments — you know how to design delivery systems that don't assume good connectivity
Deep understanding of Kubernetes — how deployments are managed, updated, and monitored in running clusters
Experience with container image distribution: OCI artifacts, image manifests, layer caching, and registry protocol
Strong understanding of mTLS, certificate lifecycle, and secure channel establishment for update delivery
Track record of setting engineering standards that other engineers adopt — protocol designs, reliability requirements, and testing standards for distributed systems
Ability to produce clear architecture documents and drive technical decisions across team boundaries (especially with the Image Build team that produces your input artifacts)
Experience mentoring mid-level engineers through design review and code review
Experience with Kubernetes operators or controller patterns — OTA delivery in Kubernetes environments often benefits from operator-style lifecycle management
Background in cybersecurity or experience building software for regulated or high-security environments
Familiarity with Fleet (or similar open-source fleet management tools) and where custom infrastructure is preferable
Experience with signed artifact delivery and chain-of-custody verification end-to-end
We are a fully remote company, and this job may require up to 5% of travel to be successful.
Qualifications
Experience:
8 years experience
