Information System Security Engineer (ISSE)
Onsite – Lorton, VA | Active TS/SCI Required | U.S. Citizenship RequiredWe are seeking Information System Security Engineers (ISSEs) to join a high-performing team of Cybersecurity, Cloud, and Systems Engineering experts supporting the development and sustainment of secure enclaves, enterprise services, and cyber network defense capabilities.
This is a hands-on engineering role weighted roughly 70% toward building security tooling from the ground up in Trellix ePO or Splunk Enterprise, and 30% toward documentation, including authoring control narratives. As an ISSE, you will conduct security assessments, engineer and automate defensive cyber capabilities, produce supporting documentation, and advise leadership on risk and mitigation. Successful candidates bring depth with technologies such as Trellix ePO, Splunk Enterprise, ACAS, Azure Automation, STIG/SCAP, and Active Directory to secure complex mission systems and ensure compliance with DoD cybersecurity standards.

• Build security tooling from scratch in Trellix ePO or Splunk Enterprise to support Cyber Threat and Defensive Operations (primary focus of the role).
• Author control narratives and supporting documentation in support of certification, accreditation, and ongoing compliance.
• Perform and review technical security assessments of computing environments to identify vulnerabilities and compliance gaps.
• Automate security monitoring, threat assessments, and reporting functions.
• Analyze system and organizational security posture trends, and provide findings to the ISSM/ISSO.
• Recommend cybersecurity measures and mitigations based on evolving threats and vulnerabilities.
• Implement security controls in alignment with DoD policies and the principles of confidentiality, integrity, availability, authentication, and non-repudiation.
• Recommend and plan modifications based on exercise results and security testing outcomes.
• Mitigate, or recommend acceptance of, identified risks and deficiencies during certification and testing activities.

• Security Clearance: Active Top Secret with SCI (TS/SCI) or above.
• Citizenship: U.S. citizenship is required pursuant to a government contract.
• Certification: IAT / IAM / IASAE Level III (DoD 8570 compliant).
• Experience: 7–10 years of demonstrated performance in related technology areas, including hands-on tooling development in Trellix ePO or Splunk Enterprise and authoring control narratives.
• Technical Expertise: Advanced skills in one or more of the following:
  • Active Directory (AD DS, ADFS, AD CS, WSUS)
  • Trellix ePO, Splunk Enterprise, STIG/SCAP, YUM, ACAS automation
  • Azure VPN Gateways, Azure Monitor / Log Analytics
• Education: Bachelor's degree in Computer Science, Engineering, or a related field; or equivalent professional experience.
• Location & Work Arrangement: Within driving distance of Lorton, VA, or willing to relocate; must be willing to work onsite.
• Travel: Up to 10%.

• 5+ years of leadership experience in cybersecurity or a related technical field.
• Technical certifications in Microsoft Azure or related cloud technologies.