Systems Administrator

Systems Administrator (Onsite – Downtown Sacramento)

Location: Downtown Sacramento, CA (100% onsite)

Reports to: IT Director

Employment Type: Full-time

About Infinium Infinium is a leading provider of gas conversion solutions and developer of eFuels projects. Its offerings include ultra‑low carbon synthetic eFuels, technology enabling monetization of flare gas and RNG, and patented technology designed to support the rapidly evolving energy industry. Infinium is a company of “firsts” – the first to produce commercial volumes of power‑to‑liquid clean eFuels; the first to develop and deploy modular gas conversion technology;

and the only clean fuels innovator offering end‑to‑end solutions to customers at every step in their energy journey. Industry leaders including Amazon, American Airlines, Borealis and IAG are customers of Infinium. Learn more at

Position Overview. The Systems Administrator will serve as the primary onsite IT support resource for our downtown Sacramento office. This role is responsible for the stability, security, and scalability of IT systems and infrastructure, while also providing advanced end‑user support as needed. This role is ideal for a service‑oriented, detail‑driven professional who enjoys troubleshooting, supporting end users, and keeping IT operations running smoothly in a growing organization.

You’ll report directly to the IT Director and partner closely with employees across the company to provide timely, high‑quality technical support.

• Serve as the primary onsite point of contact for IT support requests
• Provide in‑office support during regular business hours
• Provide Tier 1 and Tier 2 technical support for desktops, laptops, printers, mobile devices, and peripherals
• Set up, configure, deploy, and maintain employee hardware (Windows & macOS)
• Troubleshoot network connectivity, hardware, and software issues
• Escalate complex issues to external vendors or higher‑level IT resources as needed

• Administer and maintain core IT systems, including identity management, endpoint management, and SaaS platforms
• Manage user lifecycle (provisioning, deprovisioning, access reviews) across Microsoft 365, VPN, and business‑critical applications
• Monitor system performance, reliability, and security; proactively identify and remediate issues
• Maintain and improve backup, patching, and endpoint protection strategies
• Support and troubleshoot network infrastructure (Wi‑Fi, VPN, firewalls, switches) in partnership with vendors or MSPs

• Enforce security best practices including MFA, least‑privilege access, device compliance, and patch management
• Assist with audits, compliance initiatives, and security assessments
• Respond to and document security incidents and remediation actions

• Document system configurations, standards, and operational procedures
• Identify opportunities to automate routine IT tasks and improve efficiency
• Maintain IT asset lifecycle management and inventory accuracy

• 4‑7+ years of experience in IT support or systems administration IT roles
• Strong working knowledge of Windows and macOS environments
• Experience supporting Microsoft 365 Applications (Outlook, Teams, One Drive)
• Strong experience administering Microsoft 365 (Entra /Azure AD, Exchange, SharePoint, Intune)
• Solid understanding of networking fundamentals (DNS, DHCP, TCP/IP, VPNs, Wi‑Fi)
• Experience implementing and maintaining security controls and best practices
• Excellent customer service and communication skills
• Ability to work independently and manage multiple support requests
• Comfortable working onsite full‑time in a fast‑paced office environment

• Experience supporting a growing or startup‑style organization
• Familiarity with cloud infrastructure or IaaS platforms (Azure, AWS, or similar)
• Scripting or automation experience (Power Shell, Bash, etc.)
• IT certifications (Microsoft, CompTIA Network+/Security+, or similar)

Referrals increase your chances of interviewing at Infinium by 2x.