Senior Systems Administrator

Marianaminerals
San Francisco HQ +2 more
On-site

Who this role is best for

Best suited to candidates with hands-on infrastructure-building experience working in industrial/mining environments.

Best fit for

  • Candidates with a background in building infrastructure processes and systems from scratch
    — “A track record of building processes, systems, or tools from scratch
  • Individuals comfortable with cross-functional collaboration across IT, OT, and on-site stakeholders
    — “close coordination with Controls/OT engineering, Software Engineering, HR, managed service providers, and on-site stakeholders
  • Professionals with experience in multi-site environments and enterprise networking
    — “Configure and support routers, switches, firewalls, VPNs, and wireless networks across a multi-site environment

Things to consider

  • The role involves travel to multiple locations, including remote industrial sites
    — “This role requires approximately 25% travel to Mariana’s other offices and project sites
  • Candidates must be prepared to operate in a greenfield environment with limited existing documentation
    — “comfort operating with incomplete documentation and ambiguity

How to stand out

  • Highlight experience in creating governance and technical frameworks for enterprise systems
    — “Own the technical layer of SharePoint (permissions, architecture, governance)
  • Emphasize expertise in network segmentation and IT/OT boundary improvements
    — “drive network monitoring, segmentation, and IT/OT boundary improvements
  • Showcase ability to coordinate with third-party vendors and manage their performance
    — “Coordinate and hold accountable managed service providers and consultants
  • Demonstrate skills in automation and scripting, particularly with PowerShell
    — “Working proficiency in PowerShell or similar scripting for administration and automation
Pace · SteadyCollaboration · HighAutonomy · MediumDecision Impact · Team

Derived from job-description analysis by Serendipath's career intelligence engine.

What success looks like

  • Administer Microsoft 365 and Entra ID
  • Manage user access and device provisioning
  • Establish backup/disaster recovery plans
  • Coordinate with managed service providers
Typical background
5+ years in systems and network administrationDeep hands-on experience with Microsoft 365 and Entra ID

Skills & requirements

Required

Microsoft 365Entra IdCentralized AuthenticationSharepointDevice ManagementBackup And Disaster RecoveryNetwork ConfigurationIncident ResponseChange ManagementHelp Desk ProcessDocumentation

Preferred

PowershellSoftware And Saas License ManagementHardware Lifecycle ManagementNetwork MonitoringIt/ot Boundary ImprovementsManaged Service Providers Coordination

Stack & domain

Microsoft 365Entra IDSharepointDevice ManagementCentralized AuthenticationBackup And Disaster RecoveryNetwork MonitoringChange ManagementPowershellCoordinationMentorshipDocumentationTrainingITInfrastructureNetwork Administration

About the role

Original posting from Marianaminerals via Ashby

ABOUT MARIANA MINERALS

Mariana Minerals is a software-first, vertically integrated minerals company on a mission to supply the critical minerals powering modern energy, AI, and defense technologies. We’re reimagining the minerals supply chain by combining deep industry expertise with advanced software, automation, and data-driven decision-making.

THE ROLE

We are hiring a Senior Systems Administrator to take primary ownership of hands-on systems administration, infrastructure implementation, and day-to-day user support across Mariana's corporate, field, and industrial sites, freeing the Senior IT Manager to focus on architecture, budget, and cross-organizational strategy.

This is a foundational, builder-oriented role rather than a purely operational one. Core capabilities such as device management, centralized authentication, backup and disaster recovery, incident response, and change management are still being established, and this person will help build them, not just run them. Because Mariana operates a live mine, a greenfield construction site, and growing pilot facilities at the same time, the role requires close coordination with Controls/OT engineering, Software Engineering, HR, managed service providers, and on-site stakeholders to deliver urgent requirements while ensuring they support longer-term infrastructure direction.

WHAT YOU'LL DO

  • Administer Microsoft 365, Entra ID, and centralized authentication/SSO across corporate and field sites
  • Own the technical layer of SharePoint (permissions, architecture, governance) and manage user access, device provisioning, and onboarding/offboarding with HR.
  • Maintain software and SaaS license management, including renewals, entitlements, and cost optimization.
  • Establish end-to-end hardware lifecycle management — procurement, provisioning, tracking, and retirement — across offices, pilot facilities, and field sites.
  • Configure and support routers, switches, firewalls, VPNs, and wireless networks across a multi-site environment, and drive network monitoring, segmentation, and IT/OT boundary improvements.
  • Build and document backup/disaster recovery plans, security controls, vulnerability management, and a formal incident response and change management process.
  • Coordinate and hold accountable managed service providers and consultants
  • Serve as the primary escalation point for complex user and site support issues, and develop help desk process, documentation, and SLAs.
  • Mentor junior IT staff and build documentation/training that grows the team's overall technical depth.

DESIRED QUALIFICATIONS

  • 5+ years in systems and network administration with end-to-end ownership of infrastructure projects, not just ticket-based support.
  • Deep hands-on experience with Microsoft 365 and Entra ID, including centralized authentication and SSO configuration.
  • Strong networking fundamentals — VLANs/segmentation, firewalls, VPNs, wireless, routing/switching — with direct enterprise hardware experience.
  • Working proficiency in PowerShell or similar scripting for administration and automation.
  • Experience managing organization-level software/service licensing, including renewals and vendor coordination.
  • A track record of building processes, systems, or tools from scratch, and comfort operating with incomplete documentation and ambiguity.
  • Experience coordinating or overseeing managed service providers or outside consultants.
  • Preferred: experience in industrial/mining/OT-adjacent environments, familiarity with NIST SP 800-171/CMMC/ISO 27001, and experience with Apple/Mac devices and Ubiquiti networking.
  • This role requires approximately 25% travel to Mariana’s other offices and project sites.

OUR CULTURE IS BUILT ON FOUR PRINCIPLES:

Everyone Gets Home Safe. We never put speed or cost ahead of people.

Extreme Ownership. We take full responsibility for outcomes, relentlessly driving toward solutions.

Engineer Out Requirements, then Automate. We simplify, optimize, and then automate for scale.

Share Your Legos. We collaborate openly, share knowledge, and empower each other to build bigger, better solutions.

JOIN US AS WE BUILD THE FUTURE OF RESPONSIBLE MINERAL SOURCING AND SUPPLY!

Source: Marianaminerals careers (Ashby)

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