Senior Systems Administrator

Be the backbone of Realta Fusion’s internal technology. The Senior Systems Administrator owns and scales the company’s IT infrastructure, ensuring our team can work securely, efficiently, and without friction as we grow. This role blends hands-on technical execution with process-building in a fast-moving startup environment.

Realta Fusion is a rapidly growing start-up developing compact magnetic mirror fusion energy systems to address the biggest challenge of our time – tackling global climate change while ensuring a sufficient energy supply for at least ten billion people on (and off) earth. We are building a team with diverse talents dedicated to making fusion energy a real solution to humanity’s most pressing problem.

• In collaboration with managed service provider, configure, deploy, andmaintainlaptops(Mac,Windows) and peripherals for new hires and existing employees.
• Provide day-to-day IT support and troubleshooting for in-office and remote employees.
• Manage user accounts, access controls, and device lifecycle management.
• Provide off-hours support as needed.

• Own and administer Microsoft 365 licensing, user provisioning, and permissions.
• Manage company-wide cybersecurity awareness and training platform.
• Enforce security best practices, endpoint protection, and compliance with internal policies.

• Own andmaintainoffice network infrastructure, including firewalls, Wi-Fi, and VPN connectivity.
• Administer and troubleshoot VPN and network components hosted inour cloud environment.
• Partner with engineering, science, and operations teams to ensure secure and reliable connectivity.
• Collaborate with dev/ops managed service provider to support our cloud environment.

• Design, document, and continuously improve internal IT processes and policies.
• Establish onboarding/offboarding workflows and asset tracking.
• Serve as a key contributor to long-term IT strategy as the company scales.

• 7+ years of experience in systems administration or IT infrastructure roles.
• Hands-on experience managing Microsoft 365 environments and endpoint devices(Mac, Windows).
• Strong knowledge of networking fundamentals, VPNs, and cloud-based infrastructure (AWS preferred).
• Proven ability to troubleshoot a wide range of hardware, software, and network issues.
• Experience building and documenting IT processes in a growing organization.
• Familiarity with cybersecurity frameworks/certifications (i.e. NIST-CSF, ISO).

• Experience supporting start-upor high-growth environments.
• AWS certifications or equivalent cloud experience.
• Experience with identity and device management tools (e.g., Intune, MDM solutions, JAMF).
• Familiarity in supporting Linux systems.

What we are working on is hard… and hugely important. Realta Fusion is assembling a talented team bound together by a passion to solve humanity’s biggest challenge with first-of-a-kind technology. Additionally, Realta offers:

• Competitive compensation package, including equity stock options.
• Comprehensive benefits including health, dental, and vision insurance, plus a retirement savings plan.
• Flexible paid time off (PTO) to support work-life balance.
• Work and live in Madison, Wisconsin — one of America’s most livable and vibrant cities.

We value diversity as a critical factor in innovation and believe a diverse team is necessary to solve the toughest problems. We aim to create an inclusive environment that unleashes the full creativity of our team members from a wide variety of backgrounds and experiences. We provide equal employment opportunities to all individuals based on merit and without regard to race, color, religion, sex, sexual orientation, gender identity, national origin, disability, veteran status, or any other protected status under applicable laws.