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The Nuclear Company, a Series A AI-enabled startup pioneering next-generation nuclear reactor deployment, seeks a Senior Systems Administrator to securely administer and scale critical infrastructure platforms including Microsoft 365, Microsoft Entra ID, managed endpoints, AWS, and Windows/Linux server environments.
In this role, you will serve as the primary administrator and Tier 3 escalation point for assigned platforms, remediating legacy configuration risks and building automation that makes provisioning, compliance evidence, and reporting repeatable. You will partner with Infrastructure, Cybersecurity, HR, Legal, and Engineering teams to maintain reliable, auditable services and support compliance and audit-readiness objectives.
Key responsibilities include:
**Microsoft 365 and Identity Administration**: Administer and securely scale Microsoft 365 (Exchange Online, SharePoint Online, mail flow, retention, sharing, licensing). Manage Microsoft Entra ID, SSO, MFA, Conditional Access, role-based access control, and user lifecycle processes. Audit accounts, security groups, roles, and licenses; remediate orphaned identities and excessive access. Configure and operate DLP and insider-risk technical controls in partnership with Cybersecurity and Legal.
**Endpoint and Device Lifecycle Management**: Standardize enrollment and compliance through Intune across Windows, macOS, and iOS. Use NinjaOne or approved RMM platforms for endpoint monitoring and management. Maintain device naming, security baselines, configuration policies, patching, software deployment, inventory accuracy, and remediation workflows. Support complete device lifecycle from onboarding through secure offboarding.
**Cloud and Server Administration**: Administer Microsoft Azure and AWS environments, establishing scalable standards for identity, access management, security configuration, logging, monitoring, backup, and recovery. Manage Windows Server and Linux environments, including Active Directory, Group Policy, DNS, DHCP, system hardening, and patching. Maintain backup and recovery procedures with documented restoration tests.
**Automation and Process Improvement**: Build PowerShell automation (supplemented by Bash or Python) for provisioning, compliance validation, reporting, and routine administration. Develop repeatable, scalable processes for system deployment and configuration management. Leverage AI-assisted tools responsibly to improve scripting, troubleshooting, and documentation.
The ideal candidate is a hands-on technical professional with a security-first mindset who thrives in fast-paced environments and is committed to automating high-value, repeatable work. You will operate with an AI-first mindset, continuously identifying opportunities to enhance workflows and contribute to the company's strategic operating capabilities.
