Senior Linux Engineer (Classified Environment)
Date: Aug 31, 2026
Location: Oak Ridge, TN, US, 37830
Company: Oak Ridge National Laboratory
Requisition Id 16990
Overview:
The Field Intelligence Operations Division (FIOD) of the National Security Directorate (NSSD) is seeking a highly skilled, cutting-edge Senior Linux Engineer to lead the design, evolution, and modernization of secure computing environments supporting some of the nation’s most consequential national security, intelligence, and scientific missions.
This is more than a traditional Linux engineering role. You will operate at the intersection of advanced Linux architecture, cybersecurity, HPC, AI/ML, and classified computing, leading complex technical efforts and shaping secure, scalable, and resilient infrastructure where performance and reliability are mission critical.
As a senior technical contributor, you will help set technical direction, influence architecture, introduce emerging technologies, and solve the most challenging infrastructure problems across multiple security domains. You will collaborate with engineers, cybersecurity professionals, scientists, researchers, and mission partners while providing technical leadership and mentorship to others.
We are looking for someone with deep Linux expertise and an engineering mindset who enjoys architecting, building, automating, and solving difficult problems—and who can turn complex mission requirements into innovative, sustainable technical solutions.
If you want to remain hands-on while helping shape the future of secure computing, this is an opportunity to lead technically, influence what comes next, and build systems that matter.
Major Duties/Responsibilities:
- Lead the design, engineering, and modernization of secure Linux infrastructure supporting classified national security, intelligence, scientific, HPC, and emerging mission environments.
- Architect, build, optimize, and sustain enterprise Linux platforms, primarily Red Hat Enterprise Linux (RHEL) or Ubuntu, across physical and virtual environments and multiple security domains.
- Lead automation and infrastructure modernization using Ansible, Python, Bash, Git, and infrastructure-as-code practices to improve scalability, security, reliability, and operational efficiency.
- Design and implement secure computing solutions aligned with RMF, NIST 800-53, STIGs, DOE directives, and ICD 503, including system hardening, vulnerability remediation, monitoring, and compliance.
- Engineer Linux integration with enterprise identity, virtualization, storage, backup, monitoring, and security platforms, including Active Directory, LDAP, Kerberos, PKI, VMware, and KVM.
- Serve as a technical authority and escalation point for complex Linux and infrastructure challenges, performing root-cause analysis and developing sustainable engineering solutions.
- Evaluate and introduce emerging technologies, architectures, and engineering approaches, including HPC, AI/ML, GPU computing, containers, and other advanced computing capabilities.
- Collaborate with cybersecurity, networking, storage, application, HPC, and mission teams to translate complex requirements into secure, resilient, and scalable technical solutions.
- Provide technical leadership and mentorship to other engineers while helping establish engineering standards, best practices, and technology roadmaps.
- Support mission-critical operations, planned maintenance, and occasional after-hours requirements.
Basic Qualifications:
- BS degree in a related technical field and at least eight years of Linux systems engineering or administration experience. Equivalent education, experience, and relevant certifications may be considered.
- Current Top-Secret clearance with SCI eligibility.
- Advanced expertise in RHEL/Linux engineering, architecture, troubleshooting, performance optimization, and lifecycle management.
- Demonstrated experience with Ansible, Python, Bash, automation, and infrastructure-as-code practices.
- Experience designing or integrating enterprise virtualization, identity, storage, monitoring/logging, and cybersecurity capabilities.
- Demonstrated ability to independently lead complex technical efforts, make sound engineering decisions, and solve challenging cross-functional infrastructure problems.
Preferred Qualifications:
Experience in one or more of the following:
- Classified, Intelligence Community, DoD, DOE, or other highly regulated computing environments.
- HPC, AI/ML infrastructure, GPU computing, containers, Kubernetes, or advanced computing platforms.
- Enterprise Linux architecture, large-scale automation, configuration management, CI/CD, or infrastructure-as-code.
- RMF, NIST 800-53, STIG implementation, vulnerability management, and system authorization activities.
- Designing and implementing enterprise virtualization, storage, backup, resiliency, and disaster-recovery architectures.
- Leading major infrastructure modernization, technology refresh, or platform engineering initiatives.
- Relevant advanced Linux, automation, cybersecurity, virtualization, or cloud certifications.
Special Requirements:
- Visa sponsorships: Visa sponsorship is not available for this position.
- Physical Requirements: Work may involve various physical requirements and working conditions.
- Security, Credentialing, and Eligibility Requirements: Q Clearance with SCI: This position requires the ability to obtain and maintain a Secret Compartmented Information (SCI) clearance from the Department of Energy. As such, this position is a Workplace Substance Abuse (WSAP) testing designated position. WSAP positions require passing a pre-placement drug test and participation in an ongoing random drug testing program. In addition, due to the SCI, you may also be subject to random polygraph testing.
- Sensitive Access: Eligibility for access to Sensitive or Special Access Program Information
About ORNL:
As a U.S. Department of Energy (DOE) Office of Science national laboratory, ORNL has an impressive 80-year legacy of addressing the nation’s most pressing challenges. Our team is made up of over 7,000 dedicated and innovative individuals! Our goal is to create an environment where a variety of perspectives and backgrounds are valued, ensuring ORNL is known as a top choice for employment. These principles are essential for supporting our broader mission to drive scientific breakthroughs and translate them into solutions for energy, environmental, and security challenges facing the nation.
ORNL offers competitive pay and benefits programs to attract and retain individuals who demonstrate exceptional work behaviors. The laboratory provides a range of employee benefits, including medical and retirement plans and flexible work hours, to support the well-being of you and your family. Employee amenities such as on-site fitness, banking, and cafeteria facilities are also available for added convenience.
Other benefits include the following: Prescription Drug Plan, Dental Plan, Vision Plan, 401(k) Retirement Plan, Contributory Pension Plan, Life Insurance, Disability Benefits, Generous Vacation and Holidays, Parental Leave, Legal Insurance with Identity Theft Protection, Employee Assistance Plan, Flexible Spending Accounts, Health Savings Accounts, Wellness Programs, Educational Assistance, Relocation Assistance, and Employee Discounts.
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This position will remain open for a minimum of 5 days after which it will close when a qualified candidate is identified and/or hired.
We accept Word (.doc, .docx), Adobe (unsecured .pdf), Rich Text Format (.rtf), and HTML (.htm, .html) up to 5MB in size. Resumes from third party vendors will not be accepted; these resumes will be deleted and the candidates submitted will not be considered for employment.
If you have trouble applying for a position, please email ORNLRecruiting@ornl.gov.
ORNL is an equal opportunity employer. All qualified applicants, including individuals with disabilities and protected veterans, are encouraged to apply. UT-Battelle is an E-Verify employer.
Nearest Major Market: Knoxville