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Senior IT Systems Engineer

Horizon3 AI· Security and IT
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Remote$142k - $162k + equityFull-timePosted 3w ago

About the role

Security-minded IT Systems Engineer with a passion for networking, focusing roughly 60% on security, identity, and email systems and 40% on network engineering. Owns controls that protect workforce authentication, communication, and connectivity while maintaining reliable, well-documented networks. Partners with Security and Help Desk to resolve escalated issues and ensure alignment with security standards.

Responsibilities

  • Administer and secure Okta (or equivalent IdP/SSO), managing authentication policies, access provisioning, and integration with downstream applications
  • Architecting, Administering and secure the company email/collaboration platform, including mail flow rules, spam/phishing filtering, DKIM/DMARC/SPF configuration, and data loss prevention policies
  • Own operations, monitoring, and incident response for network, email and identity security controls including firewall policy, and threat detection
  • Triage incidents and remediate or escalate per incident response procedures
  • Collaborate across teams (Security and Help Desk) to resolve escalated connectivity issues, support onboarding/offboarding, and ensure infrastructure remains aligned with security standards.
  • Evaluate and recommend improvements to identity architecture, email security posture, and related tooling
  • Administer and maintain network infrastructure: switches, routers, firewalls, and wireless access points while also supporting a distributed workforce, including capacity planning and performance monitoring
  • Design and implement network changes (VLANs, routing, firewall rule changes) with minimal disruption to business operations
  • Maintain accurate documentation of network topology, configurations, and email/identity security architecture
  • Manage vendor relationships and support contracts for network, firewall, identity, and email security tooling
  • Demonstrate a commitment to integrity, process improvement, and customer satisfaction

Qualifications

  • Must have hands-on experience administering an identity/SSO platform (e.g., Okta) in a production environment, including access policies and app integrations
  • Must have experience configuring and maintaining email security controls, including SPF, DKIM, DMARC, and anti-phishing/anti-spam tooling
  • Must have experience administering a cloud email/collaboration platform (Google Workspace or Microsoft 365, or similar)
  • Must have hands-on experience administering enterprise network infrastructure (switches, routers, firewalls, VPN) in a production environment
  • Must have working knowledge of network security principles, including segmentation, firewall policy management, and VPN architecture
  • Must have experience troubleshooting complex network, identity, and email connectivity issues with minimal escalation
  • Must have experience documenting configurations, architecture diagrams, and operational runbooks
  • Must be able to scope and manage moderately complex projects end-to-end with little to no direction
  • Must have experience supporting a distributed or remote-first workforce

Skills

Required:Identity/SSO administrationEmail security configurationCloud email/collaboration administrationEnterprise network infrastructure administrationNetwork security principlesTroubleshooting complex connectivityDocumentation

Benefits

  • Health, vision & dental insurance for you and your family
  • Flexible vacation policy
  • Generous parental leave
Last updated Oct 8, 2026. Interested? Apply on the company site.

About Horizon3 AI

Only Pentesting Platform Proven in Production

Continuously assess, fix, and verify your security posture. Securing enterprises across many attack surfaces.

PentestingSecurity PostureThreat DetectionVulnerabilitiesRisk AssessmentOffensive Security
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