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Linux System Administrator/Engineer

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Location: Newport, RI

Clearance Requirement: Active Secret Clearance Required (Top Secret Preferred)

Travel: Approximately 5% CONUS travel with advance notice provided whenever possible

Position Overview: We are seeking a motivated and mission-focused Linux Systems Engineer / Administrator to support advanced tactical and cybersecurity-focused systems in a dynamic Department of Defense environment. The ideal candidate will possess strong Linux systems administration expertise, hands-on cybersecurity experience, and a willingness to work across systems engineering, platform hardening, automation, and operational support activities. This role supports the engineering, security, integration, and sustainment of mission-critical systems operating in complex networked environments. Candidates should be comfortable collaborating with cross-functional engineering teams, participating in technical reviews, and contributing to secure systems modernization efforts.

Responsibilities:

  • Administer, maintain, and secure Linux-based systems in operational and development environments
  • Implement and maintain Linux system hardening in accordance with DISA STIGs and cybersecurity best practices
  • Manage firewall configurations, networking services, privilege management, and access controls
  • Support systems engineering efforts by evaluating and implementing engineering changes and cybersecurity enhancements
  • Develop and maintain shell scripts and Python-based automation solutions to improve operational efficiency and system reliability
  • Assist with deployment and sustainment of containerized applications using Kubernetes or similar orchestration platforms
  • Participate in CI/CD pipeline development and maintenance including automated testing, SAST/DAST integration, and deployment workflows
  • Support cybersecurity assessments, vulnerability remediation activities, and RED TEAM exercises
  • Analyze penetration testing results and recommend mitigation or remediation strategies
  • Collaborate with engineering, cybersecurity, and operations teams during trade studies, integration efforts, and technical reviews
  • Provide on-site technical support during testing events, system installations, and fleet or vendor visits as required
  • Maintain documentation related to system configurations, engineering changes, security controls, and operational procedures
  • Develop and maintain technical documentation including system procedures, engineering artifacts, implementation plans, test plans, and test reports
  • Support system integration and Test & Evaluation (T&E) activities through test planning, execution support, documentation, and reporting
  • Coordinate with engineering and cybersecurity teams to document system changes, validation activities, and remediation efforts

Required Qualifications: Significant experience with Linux systems administration in enterprise or mission-critical environments

  • Strong understanding of:
  • Linux networking
  • Linux filesystems
  • Privilege and identity management
  • System hardening and STIG compliance
  • Bash shell scripting
  • Python programming

o Network enumeration

o Privilege escalation

  • Familiarity with CI/CD pipelines and DevSecOps concepts including:
  • Automated tooling
  • Unit testing
  • Static and dynamic application security testing (SAST/DAST)
  • Experience working in containerized environments using Kubernetes or equivalent orchestration tools
  • Ability to troubleshoot complex Linux systems and networking issues
  • Strong technical writing and verbal communication skills
  • Active Secret Security Clearance or eligibility for reinstatement
  • Experience managing and maintaining virtualized environments including virtual machine (VM) creation, configuration, administration, and lifecycle management

Preferred Qualifications

  • Advanced Linux expertise including:
  • Filesystem administration and manipulation
  • Encryption and key management
  • SELinux administration
  • ACL and IMA labeling
  • Experience supporting tactical networks, critical infrastructure, or defense systems
  • Experience working within a Scaled Agile Framework (SAFe) environment
  • Familiarity with undersea domain systems or submarine platforms
  • Prior experience supporting DoD cybersecurity initiatives or classified environments
  • Experience with virtualization technologies and VM management in enterprise or lab environments (VMware, KVM, VirtualBox, Hyper-V, or equivalent)

Education

  • Bachelor’s degree in Engineering, Information Systems, Computer Science, Cybersecurity, or related technical discipline preferred or equivalent military or industry experience may be considered in lieu of degree

Why Join Us: You will work alongside highly skilled engineers and cybersecurity professionals supporting mission critical defense systems that directly contribute to national security. This role offers opportunities for technical growth, hands-on operational support, and participation in cutting-edge cybersecurity and systems engineering initiatives.

Job Types: Contract, Full-time

Education:

  • Bachelor's (Required)

Experience:

  • Cybersecurity: 1 year (Required)
  • Systems Engineering: 2 years (Required)
  • Linux Administration: 3 years (Preferred)

License/Certification:

  • CompTIA Linux+ (Required)

Security clearance:

  • Secret (Required)

Work Location: In person

Skills

See also

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