Sr. Cybersecurity Engineer (ISSE / Product Security Engineering)

Istari Digital delivers a model-based digital engineering platform that enables defense and aerospace teams to design, integrate, and operate complex systems. We are hiring an Information System Security Engineer (ISSE) to serve as the technical implementer of cybersecurity within our platform, directly applying security requirements to system architecture and the software development lifecycle.

Responsibilities:

• Implement NIST 800-53 / 800-171 security controls directly into system design and platform architecture
• Lead system hardening and secure configuration across platform components
• Embed security into the engineering workflow (DevSecOps)
• Perform: System Patching
• STIG implementation and validation
• Vulnerability scanning (ACAS/Nessus)
• POA&M management and remediation tracking
• Partner with engineering teams to: Secure APIs, services, and data pipelines
• Enforce least privilege, identity, and access controls
• Support deployment into: SIPR / JWICS / SAP environments
• Identify and remediate security gaps before they reach customer environments

Requirements:

• Active TS clearance with SCI eligibility
• DoD 8570/8140 certification (Security+ minimum)
• 5+ years in cybersecurity with hands-on implementation experience
• Direct experience with NIST 800-53 / 800-171
• Direct experience with DISA STIGs
• Direct experience with ACAS/Nessus
• Background in Systems Administration, Network Engineering, or SOC → transitioned into security
• Experience working in Classified environments (SIPR, JWICS, SAP)
• Poly
• CISSP/CASP+/CISM preferred
• Track record of stability (2+ years per role preferred)
• Comfortable in a startup environment