# Senior System Administrator at Radiant

- Company: Radiant
- What the company does: Radiant builds Kaleidos, a portable, factory-built nuclear microreactor that delivers a megawatt of clean power anywhere it is needed. Backed by a16z, Felicis and USV.
- Company website: https://www.radiantnuclear.com
- Type: Startups
- Level: Senior
- Location: El Segundo, CA
- Work setup: On-site
- Pay: $134K to $190K base salary per year (USD)
- Posted: 2026-09-12
- Apply by: 2026-10-27
- Apply: https://jobs.ashbyhq.com/radiant-industries/44491ec2-be9c-481e-a1d7-fe631abf1501
- Page: https://www.1752.vc/careers/jobs/radiant-senior-system-administrator/

## About the role

Radiant is seeking a Senior Systems Administrator to own the systems that keep the company running day-to-day within Microsoft 365 GCC High. You'll own the tenant, build our identity and access automation from the ground up in an Entra-native environment with no on-prem Active Directory or Group Policy, and manage the endpoint, email security, and SaaS infrastructure the business runs on. You'll implement and evidence the technical controls behind our CMMC assessment as part of the normal job, not a detour.

## What they're looking for

- Bachelor's degree in Information Technology, Computer Engineering, Cybersecurity, or a similar field (4 years of work experience in lieu of a degree)
- 7+ years administering and engineering production systems
- Deep, hands-on experience across the responsibilities above: GCC High tenant administration, Entra, self-built IAM automation, Intune without Group Policy, email security and Purview, and SaaS/AWS administration
- Solid networking fundamentals: VLANs, routing, firewall policy, DNS/DHCP, VPN, wireless
- Treats compliance control implementation and evidence collection as normal work
- Service is the job, tier-1 handles day-to-day support, but nobody's too senior to help the person at their desk

Tags: Engineering