Istari Digital
Cybersecurity Engineer – Classified Infrastructure (Customer Success)
Istari DigitalFrance6 hours ago
Full-timeInformation Technology
Security Clearance: Active TS required with SCI eligibility (Polygraph a plus)
About Istari Digital
Istari Digital delivers a model-based digital engineering platform used by defense and aerospace organizations to design and operate mission-critical systems. Our platform is deployed into classified and high-security environments, where cybersecurity is foundational—not optional.

Role Overview
We are hiring a Cybersecurity Engineer to support customer deployments in classified environments, ensuring Istari’s platform operates securely, compliantly, and reliably in real-world mission systems.

This role sits within Customer Success and focuses on hands-on system and infrastructure security—not just documentation or policy.

Depending on your background, you may lean more toward:


  • System hardening (Windows/Linux)
  • Secure network infrastructure (classified environments)



In this role YOU will be the difference between a platform that looks secure on paper, and one that actually works inside real classified mission environments.
What You'll Do

  • Deploy and secure Istari’s platform in:
    • SIPR, JWICS, and air-gapped environments






  • Implement and validate:
  • DISA STIGs
  • NIST 800-53 / 800-171 controls



  • Perform hands-on security work, including:
  • System hardening (Windows & Linux)
  • Vulnerability scanning (ACAS/Nessus)



  • STIG validation and remediation



  • POA&M management



  • Design, configure, or support secure network architectures, including:
  • Segmentation, boundary defense, and routing in classified environments
  • Troubleshoot and resolve:
  • Security configuration issues
  • Connectivity and compliance blockers
  • Work directly with:
  • Customer security teams (ISSO, ISSM, AO, SCA)
  • Program and infrastructure teams
  • Provide feedback to engineering on:
  • Real-world deployment constraints
  • Security gaps and improvements



Required Qualifications
Must-Haves

  • Active TS clearance with SCI eligibility



Security+ (required) — CISSP, CISM, or CASP+ preferred


  • 4+ years of hands-on experience in cybersecurity, system administration, or network engineering
  • Direct experience with:
  • NIST 800-53 / 800-171
  • DISA STIGs



  • Experience operating in:
  • Classified environments (SIPR, JWICS, SAP)



Your Background (You may come from one or both areas)
Experience Profile A: System Hardening (System Administration)

  • Strong experience securing:
    • Windows and/or Linux systems






  • Hands-on System Patching, STIG implementation and validation
  • Experience running scans, remediating findings, and managing POA&Ms



Experience Profile B: Secure Infrastructure (Network Engineering)

  • Experience designing or supporting:
    • Secure network architectures in classified environments






  • Knowledge of:
  • Network segmentation, boundary defense, and secure connectivity
  • Familiarity with STIGs for network devices and infrastructure



What Makes You a Strong Fit

  • You started in a technical role (SysAdmin, Network, SOC) and moved into security
  • You’ve done real, hands-on work—not just compliance oversight
  • You’re comfortable working:
    • In deploying emerging technology into real-world classified environments


  • Under time pressure to meet deployment or mission deadlines



  • You stay long enough to see systems through deployment and accreditation



  • You’re comfortable in a startup environment—scrappy, fast-moving, and collaborative
  • You’re willing to do the work needed to get across the finish line, even when it’s manual



We may use artificial intelligence (AI) tools to support parts of the hiring process, such as reviewing applications, analyzing resumes, or assessing responses. These tools assist our recruitment team but do not replace human judgment. Final hiring decisions are ultimately made by humans. If you would like more information about how your data is processed, please contact us.

(may be additionally eligible for stipend, one time incentive, or % differential for clearance)

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