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Istari Digitalistaridigital.com

Cybersecurity Engineer – Classified Infrastructure (Customer Success)

$116k – $174k YearlyUnited States (Remote)Full-time4h ago

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