Linux System Administrator/Engineer

Crest Security Assurance; Newport (RI); On-site; USD 125,000 - 130,000; Full time

Job summary

Crest Security Assurance is seeking a Linux Systems Engineer/Administrator to support DoD systems in Newport, RI. The role emphasizes Linux administration, system hardening, and automation, with duties spanning engineering, cybersecurity, and operations.

The successful candidate will implement DISA STIGs, manage virtualization and containerized deployments with Kubernetes, and contribute to CI/CD and security testing. A Secret clearance is required or eligible for reinstatement.

Qualifications

• Significant Linux administration experience in enterprise or mission-critical environments.
• Strong understanding of privilege/identity management and STIG compliance.
• Experience with Bash scripting and Python programming.
• Familiarity with CI/CD pipelines and DevSecOps concepts including automated tooling, unit testing, SAST/DAST.
• Experience with containerized environments using Kubernetes or similar orchestration tools.
• Ability to troubleshoot complex Linux systems and network issues.
• Active Secret clearance or eligibility for reinstatement.

Responsibilities

• Administer, maintain, and secure Linux-based systems in operational and development environments.
• Implement Linux system hardening per DISA STIGs and cybersecurity best practices.
• Manage firewall configurations, networking services, privilege management, and access controls.
• Develop shell scripts and Python automation to improve efficiency and reliability.
• Support deployment and sustainment of containerized apps using Kubernetes or similar tools.
• Contribute to CI/CD pipelines, testing, and automated security testing integration.
• Support cybersecurity assessments, vulnerability remediation, and RED TEAM exercises.
• Document system configurations, security controls, and procedures.
• Collaborate across engineering, cybersecurity, and operations teams during reviews.

Skills

Linux administration

Privilege management

System hardening

Bash scripting

Python

CI/CD / DevSecOps

SAST/DAST

Kubernetes

Troubleshooting Linux

Technical writing

Education

Bachelor's degree or equivalent experience

Tools

Kubernetes

VMware / virtualization

Job description

Salary Range: $125,000.00 To $130,000.00 Annually

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:
• Privilege and identity management
• System hardening and STIG compliance
• Bash shell scripting
• Python programming
• 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

• Filesystem administration and manipulation
• Encryption and key management
• 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)