Systems Engineer - Windows Domain & Integration We are seeking a Senior Systems Engineer responsible for the design, build, integration, and lifecycle management of Windows-based systems within complex enclave environments. This role focuses on delivering and sustaining reliable, secure, and interoperable system capabilities across Windows server infrastructure, domain services, and integrated COTS applications. The position centers on Windows domain engineering, including Active Directory administration, Group Policy architecture, and integration of core services such as Citrix, Microsoft Exchange, and Microsoft SQL Server. The role also includes support for endpoint security enforcement using Trellix ePolicy Orchestrator (ePO), as well as certificate and PKI services that support authentication and secure communications across systems. This environment consists of multiple independent systems and domains supporting a wide range of COTS and engineering applications. These may include collaboration and workflow tools (such as Jira, Confluence, and SharePoint) as well as engineering platforms (such as SolidWorks and MATLAB). Deep expertise in any single application is not required; success in this role depends on the ability to integrate and sustain interoperability across diverse systems. The role requires strong engineering discipline, the ability to manage multiple concurrent efforts, and the flexibility to support both design and operational activities as needed. Responsibilities Include: Windows Domain Engineering & Systems Lifecycle - Design, build, integrate, and maintain Windows-based systems across enclave environments - Engineer system-level solutions spanning domain services, server infrastructure, and integrated applications - Support modernization and sustainment of existing systems and platforms Active Directory & Domain Services Administration - Administer and maintain Active Directory environments supporting domain-joined systems and services - Engineer secure and scalable Windows Server environments supporting core services - Support PKI and certificate services, including certificate lifecycle management and integration with domain and application services - Utilize PowerShell to automate routine administrative tasks, streamline operational workflows, and support system configuration and troubleshooting activities - Create and maintain technical documentation including design artifacts and as-built documentation for system designs and integrations Group Policy Design & Management - Design, implement, and maintain Group Policy Objects (GPOs) to enforce configuration and security standards - Troubleshoot Group Policy inheritance, replication, and application issues - Maintain baseline configurations for domain-joined systems across the enclave Application & COTS Integration - Integrate and support systems within Active Directory environments, including Microsoft Exchange, Microsoft SQL Server, and Citrix environments - Support authentication, authorization, and service integration across diverse COTS and engineering platforms - Ensure interoperability between infrastructure services and mission applications, including certificate-dependent services Endpoint Security & Systems Management - Support endpoint security configuration and policy enforcement using Trellix ePolicy Orchestrator (ePO) - Ensure systems comply with established security baselines and organizational requirements - Collaborate with security teams to support vulnerability remediation and enforcement activities Systems Integration & Collaboration - Work closely with application owners, network engineers, storage teams, and security teams to support integration across enclave systems - Resolve cross-platform integration challenges spanning identity, infrastructure, and application layers - Support troubleshooting across interconnected systems Operational Support & Sustainment - Provide operational support as required to maintain stability of domain and server environments - Support incident response and infrastructure issue resolution as part of engineering ownership Required Experience, Skills, and Education: - Requires a Bachelor degree and at least 8 years of experience or Master and at least 6 years of experience OR at least 12 years of experience in lieu of degree. - Must have a TS/SCI with poly to be considered. - Must have strong knowledge of Windows Active Directory, Group Policy and must understand WSUS and third party software patching. - Integrate and support systems within Active Directory environments, including Microsoft Exchange, Microsoft SQL Server, and Citrix environments Preferred Experience, Skills, and Education: The following skills are not primary ownership areas but are valuable for effective collaboration across enclave infrastructure teams: - NetApp storage systems and SAN concepts - Nutanix virtualization and HCI environments - FSLogix profile/containerization in VDI environments - Citrix virtualization and application delivery concepts - Multi-factor authentication platforms and identity integration patterns - Data center replication and disaster recovery concepts (replication, failover, site resilience) - Development and maintenance of operational runbooks and procedures Clearance Required: - TS/SCI with Poly - You will be required to pass both a customer required and administered medical and psychological screening, as a condition of employment Original Posting: June 3, 2026 For U.S. Positions: While subject to change based on business needs, Leidos reasonably anticipates that this job requisition will remain open for at least 3 days with an anticipated close date of no earlier than 3 days after the original posting date as listed above. Pay Range: Pay Range $107,900.00 - $195,050.00 The Leidos pay range for this job level is a general guideline only and not a guarantee of compensation or salary. Additional factors considered in extending an offer include (but are not limited to) responsibilities of the job, education, experience, knowledge, skills, and abilities, as well as internal equity, alignment with market data, applicable bargaining agreement (if any), or other law.