System Administrator III - Windows/macOS

Job Description

Job Description

About the Opportunity

The Systems Administrator - Windows/macOS is responsible for administering, securing, and optimizing both enterprise Windows Server and macOS environments across physical, virtual, and cloud-connected infrastructures in a remote and on-site work environment. This dual-platform role manages core Microsoft technologies (Active Directory, Group Policy, DNS, DHCP, Microsoft Entra ID) alongside macOS device administration, identity integration, and mobile device management (MDM) platforms. 

Success in this role is demonstrated by maintaining secure and highly available systems across both operating systems, effectively resolving complex technical issues, implementing automation and security improvements, ensuring compliance with federal requirements, and supporting mission objectives through collaboration.

What You Will Do in This Role

The System Administrator III - Windows/macOS administers and secures enterprise Windows and macOS environments, supporting identity, infrastructure, cloud, and endpoint systems while ensuring federal compliance, automation, vulnerability management, troubleshooting, and cross-functional IT operations.

• Administer, configure, maintain, and optimize enterprise Windows Server and macOS environments across physical, virtual, and cloud-connected systems. Manage identity and infrastructure services including Active Directory, Group Policy, DNS, DHCP, Microsoft Entra ID, and MDM platforms (Jamf Pro, BigFix, MECM, ManageEngine, Intune).
• Develop and maintain OS standards, security configurations, device management policies, and enterprise architecture for Windows and Apple systems.
• Implement federal security requirements (RMF, DISA STIGs), including patching, access controls, vulnerability remediation, and DoD CAC authentication.
• Support endpoint lifecycle management and cloud/virtual environments, including device deployment and administration across VMware, Hyper-V, Azure, and AWS.
• Monitor system performance and troubleshoot complex cross-platform issues involving hardware, OS, applications, networking, and user configurations.
• Develop and maintain automation and Infrastructure as Code using PowerShell, Python, Bash, AppleScript, Terraform, and Ansible.
• Conduct vulnerability assessments, analyze findings, and coordinate remediation to support compliance audits and continuous monitoring.
• Collaborate with cybersecurity, network, infrastructure, and end-user teams to ensure secure, integrated operations and resolve cross-functional issues.
• Prepare technical documentation including architecture diagrams, procedures, scripts, and troubleshooting guides; provide status updates to the Federal IT Lead and stakeholders.

What You Will Bring

• Bachelor’s degree in Computer Science, Information Technology, or related field (or equivalent experience).
• 8+ years of systems administration experience, including extensive Windows Server administration and 5+ years supporting enterprise macOS environments.
• Extensive experience with Microsoft ecosystem technologies, including Windows Server, Active Directory, Group Policy, DNS, DHCP, and Microsoft Entra ID.
• Experience managing macOS devices using MDM platforms such as Jamf Pro, Microsoft Intune, Kandji, or similar solutions.
• Experience with federal security and compliance frameworks, including NIST, FISMA, and enterprise vulnerability management programs.
• Strong automation and scripting skills using PowerShell, Python, Bash, and related automation frameworks.
• Experience supporting virtualization and cloud environments, including Microsoft Azure, AWS, VMware, and Hyper-V.

Work authorization/security clearance requirements

• Ability to obtain a security clearance.

Work Environment

• This work is normally completed in a remote and on-site environment.

Physical Demands

• Prolonged periods of sitting at a desk and working on a computer.
• Must be able to access and navigate each department at the organization's and client facilities.

Travel Required

• Travel may be required on an as-needed basis.

Proficiency Requirement

• The employee is expected to demonstrate proficiency in all essential job functions, tools, and processes related to this position within the first 90 days of employment. This includes acquiring a thorough understanding of job-specific responsibilities, systems, and workflows as outlined during onboarding and training. Failure to meet this requirement may result in additional training, reassessment, or other actions as deemed necessary by management.

GAMA-1 also offers a variety of benefits, including health insurance coverage, life and disability insurance, 401(k) savings plan, training and career development opportunities, paid holidays and paid time off (PTO - to cover vacation, illness or disability, appointments, emergencies or other situations that require time off from work). For more information click here.

ABOUT GAMA-1

GAMA-1 is a rapidly growing technology business that is based in Greenbelt, Maryland. GAMA-1 Technologies provides strategic information assurance, information security, and business enterprise and networking solutions to the Federal Government. Our success is based on the utilization of industry and agency standards, establishment of standardized processes, and IT Services expertise. At GAMA-1, we believe employees should grow, achieve, and develop just as the company grows, achieves, and develops. GAMA-1 is committed to providing our employees with opportunities for career advancement throughout their employment. For more information, visit

GAMA-1 is an Equal Opportunity Employer and all qualified applicants will receive consideration for employment without regard to: veteran status, uniformed servicemember status, race, color, religion, sex, sexual orientation, gender identity, age, pregnancy (including childbirth, lactation and related medical conditions), national origin or ancestry, citizenship or immigration status, physical or mental disability, genetic information (including testing and characteristics), domestic violence victims, political orientation, status as a smoker or tobacco user, hairstyle, use of a service animal, education status, familial status, HIV/AIDS status, height, weight, reproductive healthcare decisions or any other category protected by federal, state or local law.