Position Overview

We are seeking a Senior Infrastructure Engineer to support and operate mission-critical, enclave-based environments across on-premises VMware infrastructure and AWS cloud. 

This role sits at the center of a high-security, high-availability ecosystem, supporting systems where downtime has real operational impact. You will be responsible for owning, stabilizing, and improving a complex hybrid environment consisting of both legacy and modern platforms. 

This is not a passive support role-this is for someone who can step in, take control of the environment, and drive reliability and performance forward. 

Clearance Requirement

• Active TS/SCI with Poly security clearance required

• Must be eligible to work in restricted / air-gapped environments

What You’ll Own

• Two standalone/enclave Windows domains:  

• On-prem VMware-based infrastructure

• AWS-hosted environment

• A 24/7 mission-critical system footprint

• Core enterprise services: identity, storage, compute, backup, and security tooling  

• Environments with limited external connectivity and strict security controls

Key Responsibilities

• Administer and maintain Windows-based infrastructure across enclave environments  

• Manage VMware vCenter / ESXi (host performance, VM lifecycle, resource optimization)  

• Support AWS cloud infrastructure (EC2, VPC, storage, IAM fundamentals)  

• Maintain and troubleshoot Active Directory, Group Policy, and identity systems

• Oversee patching and system compliance via WSUS and SCCM  

• Administer Microsoft Exchange and Citrix environments

• Maintain DNS, networking, and core infrastructure services

• Support and optimize SAN storage environments

• Manage backup and recovery operations using Rubrik  

• Support and troubleshoot security platforms, including:  

• Trellix ePO  

• Rapid7  

• Security Onion IDS  

• Centrify  

• Perform deep-dive troubleshooting and root cause analysis across systems  

• Maintain system documentation, SOPs, and incident response procedures

• Identify and implement infrastructure improvements and automation opportunities

Environment Characteristics

• Air-gapped / enclave networks

• Hybrid on-prem (VMware) + AWS cloud

• Legacy mission systems with modernization constraints  

• Security-first architecture with strict compliance requirements

• High uptime expectations with minimal tolerance for disruption  

Required Qualifications

• Must have at least 12 years of experience in systems engineering or infrastructure engineering

• Active TS/SCI with Poly

• Strong experience supporting Windows enterprise environments

• Proven experience in high-availability / mission-critical systems

• Experience operating in restricted, regulated, or air-gapped environments

• Strong troubleshooting skills across OS, virtualization, networking, and storage layers

• Ability to work independently and take ownership of complex systems

Core Technical Expertise

• Operating Systems

• Windows Server (2016/2019/2022)  

• Windows 11  

• Linux (Rocky Linux, Red Hat)  

• Virtualization & Cloud

• VMware vCenter / ESXi  

• AWS (EC2, VPC, storage, IAM basics)  

• Core Infrastructure

• Active Directory & Group Policy  

• DNS / networking fundamentals  

• SAN Storage  

• Systems Management

• SCCM, WSUS  

• Microsoft Exchange  

• Citrix  

• Security Tooling

• Trellix ePO  

• Rapid7  

• Security Onion IDS  

• Centrify  

• Backup & Recovery

• Rubrik  

• Preferred

• PowerShell / Bash scripting  

• Experience with compliance frameworks (STIGs, RMF, NIST)  

Operational Expectations

• Support a 24/7 operational environment

• Participate in a rotational on-call schedule

• Must be able to respond (Return-to-Base) within 2 hours, including travel if required  

• Support after-hours maintenance windows and incident response

What Sets This Role Apart

• Direct ownership of mission-critical systems supporting real-world operations

• Opportunity to work in secure, high-impact environments

• Exposure to both legacy infrastructure challenges and modernization efforts

• Ability to drive meaningful improvements, not just maintain status quo  

Who We’re Looking For an Engineer Who: 

• Has operated in cleared environments and understands the constraints  

• Can walk into a complex, imperfect system and make it better  

• Doesn’t wait for direction-identifies problems and solves them

• Is trusted to handle high-pressure situations without supervision

• Brings both technical depth and operational accountability

Bottom Line

If you’re looking for a role where: 

• Your work directly supports critical operations

• You have real ownership and responsibility

• And your impact is immediate and visible

If you're looking for comfort, keep scrolling. At Leidos, we outthink, outbuild, and outpace the status quo - because the mission demands it. We're not hiring followers. We're recruiting the ones who disrupt, provoke, and refuse to fail. Step 10 is ancient history. We're already at step 30 - and moving faster than anyone else dares.

Original Posting:

Pay Range:

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.