Senior Platform Engineer

Role Overview

The Sr. Platform Engineer — Identity & Modern Workplace is the senior technical owner of three platform domains at Radiant: identity & access, endpoint management, and productivity & collaboration. You'll architect and operate these domains as integrated platforms — designing how people authenticate, how their devices are governed, and how they collaborate securely — and you'll continue to own and evolve those platforms as Radiant grows.

Radiant currently runs on the Microsoft platform across identity, endpoint, and productivity domains — Entra , Intune, Microsoft 365, SharePoint, and Exchange Online — and the bulk of day‑to‑day work happens in that stack. Familiarity with the current stack is valuable; rigid attachment to it is not. Mac devices are part of the fleet (~30) and are managed through the same MDM platform as Windows.

• Identity & Access
  • Own the identity platform end‑to‑end: identity lifecycle (joiners, movers, leavers), directory and group strategy, and hybrid identity when required.
  • Design and operate zero‑trust access—conditional/contextual access policies, modern authentication, MFA, and risk‑based controls—in partnership with Sec Ops.
  • Govern application identity: SSO and federation patterns, OAuth/OIDC app registrations and consent, service principals, and third‑party SaaS integration (including SCIM provisioning where supported).
  • Define and maintain access architecture—RBAC models, role assignments, permission boundaries, privileged access patterns, and access reviews.
• Endpoint & Device Posture
  • Own modern device management for the fleet—enrollment, configuration, compliance, application delivery, and update strategy—across both Windows and macOS.
  • Establish and enforce device posture as a foundation for conditional access and zero‑trust enforcement.
  • Build provisioning experiences that minimize friction for end users while meeting security and compliance requirements.
• Productivity & Secure Collaboration
  • Own the collaboration and productivity platform—email, messaging, file collaboration, and content management—including governance, lifecycle, and external sharing models.
  • Implement data protection patterns (DLP, sensitivity labels, retention) in partnership with Sec Ops, who owns the policy direction.
• Platform Modernization
  • Lead the technical design and execution of Radiant's move from legacy on‑premises identity and endpoint management to a modern, cloud‑native model.
  • Apply working knowledge of legacy on‑prem patterns (Active Directory, Group Policy, traditional MDM/imaging) to navigate, document, and decommission legacy artifacts during transition. Ongoing administration of legacy on‑prem systems is not the focus of this role.
  • Document target‑state architecture, migration plans, rollback strategies, and operational runbooks.
  • Continuously evaluate the platform stack against business needs—recommend integration, replacement, or expansion when the current tooling is no longer the right fit.
• Automation, IaC & AI‑Enabled Engineering
  • Drive automation across managed platforms using a modern scripting and API toolkit—Power Shell and Microsoft Graph for the M365 ecosystem, Python and REST APIs broadly, and Infrastructure-as-Code (Terraform or equivalent) for declarative platform configuration where it provides leverage.
  • Apply AI tooling fluently across the day‑to‑day—Claude, Gemini, and Microsoft Copilot are all in active use at Radiant—for scripting and IaC generation, design exploration, policy and log analysis, runbook and documentation drafting, and accelerated troubleshooting.
  • Use Microsoft Copilot where it is native to the M365 ecosystem and provides capability the general‑purpose AI tools cannot—e.g., Security Copilot in incident workflows or Copilot‑assisted administration inside Intune and M365 admin centers.
• Operations & Team
  • Maintain comprehensive documentation of managed platforms—architecture, configuration, runbooks, and SOPs.
  • Execute change management for platform changes—maintenance windows, rollout planning, and communication.
  • Own license management and capacity forecasting for platforms under your domain.
  • Provide hands‑on T2/T3…