Senior IT Systems Engineer

CultureMill Recruiting; Los Angeles (CA); On-site; USD 120,000 - 160,000; Full time

Job summary

CultureMill Recruiting is seeking a Senior IT System Engineer for a world-class hard-tech company in LA. You will bridge people, factory, and data, owning identity, endpoints, servers, storage, cloud, network, and security.

This hands-on role treats IT as a product and requires a practical mindset. From on-site work five days a week in Los Angeles, you’ll manage hybrid Microsoft 365, Entra ID, Azure, and on-prem Active Directory while scaling virtualization, Kubernetes, and secure networking

Qualifications

• 7+ years in systems administration or infrastructure engineering.
• 3+ years in a senior or lead role.
• Experience with both on-prem and cloud, across Windows and Linux.
• Hybrid M365, Entra ID, and Intune; Windows Server DNS/DHCP/RADIUS; Ubuntu and Red Hat.

Responsibilities

• Operate hybrid Microsoft 365, Entra ID, Azure, and Intune alongside on-prem Active Directory.
• Build and maintain Windows Server and hardened Ubuntu and Red Hat servers.
• Run virtualization and SAN storage, from provisioning to capacity planning.
• Own AWS infrastructure and administer Kubernetes on-prem and in EKS.
• Design and maintain the Layer 2/3 network and its segmentation, including OT zones.
• Operate Defender XDR, Sentinel, and pfSense, from detection tuning to incident response.
• Build automation and custom tools; join the on-call rotation.

Skills

Systems administration

Infrastructure engineering

Windows/Linux platforms

Hybrid M365 EntraID Intune

Cloud + on-prem

Networking L2/L3

PowerShell Bash

On-site LA

Education

Degree in computer information systems, computer science, or computer engineering

Tools

vSphere

Hyper-V

OpenShift

SAN storage (iSCSI/NFS)

Pure Storage

HPE 3PAR

AWS

Azure

GCP

Kubernetes

Defender XDR

Sentinel

pfSense

Job description

The most advanced hardware in the world is being held back by how it gets made. Our client is fixing that. From their facility at the heart of LA's hard-tech corridor, they're building AI-driven factories that produce precision components for rockets, defense systems, and the next generation of frontier hardware. Their platform combines proprietary production hardware with real-time sensing, machine learning, and on-site GPU compute, so the factory sees, learns, and corrects as every part is built. Backed by top-tier investors including NVIDIA, the company is past proof-of-concept: demand outpaces capacity, and the team is scaling fast.

As the Senior IT System Engineer you'll build and run the systems that connect the people, the factory, and the data: identity, endpoints, servers, storage, cloud, network, and security. IT here is part of the product. The role suits a broad, hands-on engineer with a \"no job too big or small\" mindset who would rather build a smart solution than buy an expensive one.

What You'll Do

• Run hybrid Microsoft 365, Entra ID, Azure, and Intune alongside on-prem Active Directory
• Build and maintain Windows Server and hardened Ubuntu and Red Hat servers
• Run virtualization and SAN storage, from provisioning to capacity planning
• Own AWS infrastructure and administer Kubernetes on-prem and in EKS
• Design and maintain the Layer 2/3 network and its segmentation, including OT zones
• Operate Defender XDR, Sentinel, and pfSense, from detection tuning to incident response
• Build automation and custom tools, act as senior escalation, and join the on-call rotation

Who You Are

• 7+ years in systems administration or infrastructure engineering, including 3+ in a senior or lead role
• Hands-on experience with both on-prem and cloud (cloud-only backgrounds won't be a fit), across Windows and Linux
• Hybrid M365, Entra ID, and Intune; Windows Server DNS, DHCP, and RADIUS; Ubuntu and Red Hat
• vSphere, Hyper-V, or OpenShift, and SAN over iSCSI/NFS (Pure Storage, HPE 3PAR)
• AWS, Azure, or GCP, and Kubernetes on-prem and in the cloud
• Layer 2/3 networking (VLANs, MLAG, LACP), and Defender XDR, Sentinel, and pfSense
• PowerShell and Bash scripting, and clear written communication
• Able to work on-site in Los Angeles five days a week

Nice to Have

• HashiCorp Vault, Argo CD, Ansible, or Python
• Siemens Teamcenter or SQL Server administration
• Physical security systems (CCTV, access control)
• Degree in computer information systems, computer science, or computer engineering