Senior Windows Platform Engineer | Contract | Hybrid, Agoura Hills

About us:

Working at Tech Holding isn't just a job, it's an opportunity to be a part of something bigger. We are a full-service consulting firm that was founded on the premise of delivering predictable outcomes and high-quality solutions to our clients. Our founders and team members have industry experience and have held senior positions in a wide variety of companies – from emerging startups to large Fortune 50 firms – and we have taken our combined experiences and developed a unique approach that is supported by the principles of deep expertise, integrity, transparency, and dependability.

The Role:

We are looking for a Senior Windows Engineer for a project-based assignment to strengthen the stability and resiliency of a business-critical Windows environment across Active Directory, DNS, authentication, automation, observability, security, and disaster recovery. This is a hands-on platform engineering role that combines deep Active Directory and Kerberos expertise with Windows automation, cloud infrastructure, and Infrastructure as Code. You will work across directory services, authentication, golden image and patching pipelines, PowerShell automation, PKI, configuration management, and recovery capabilities while helping improve the reliability and resilience of the overall Windows platform. The ideal candidate is a Windows platform and automation engineer rather than a traditional Windows administrator, with strong cloud fluency and experience managing infrastructure through code and automation.

Key Responsibilities:

• Improve Active Directory and DNS resilience, including replication topology and health, FSMO roles, DFS-R, NTDS, AD-integrated DNS, and domain controllers running as cloud instances.
• Support the estate's migration from NTLM to Kerberos, ensuring both protocols can operate without an outage during the transition.
• Work with service principal names and duplicate-SPN failure modes, constrained delegation, AES over RC4 through the supported-encryption-types attribute, managed and group managed service accounts, and reverse DNS.
• Support identity integration across the estate, including LDAP for non-Windows hosts, desktop single sign-on via Kerberos passthrough with constrained delegation, cloud single sign-on, and brokered application identity.
• Support and improve the golden image and patch pipeline, including image bake automation, CI-scheduled builds, promotion, deprecation, deregistration, and CVE-driven rebuilds.
• Improve Windows observability, including infrastructure agents, Windows service and event-channel collection, script-derived metrics, domain controller service health, replication status, and operational log-channel forwarding.
• Develop and maintain PowerShell automation supporting Windows platform operations and resiliency.
• Support Infrastructure as Code and configuration management, including Chef, Ansible, Systems Manager, guardrail policies, pipeline pre-deploy validation, and OpenTofu.
• Support multi-account rebuild, guardrail policies, and module compliance.
• Strengthen security and data-protection controls, including encryption by default on block storage, key management, web-tier protection, and instance metadata hardening.
• Improve PKI and certificate services resilience, including certificate authority recovery posture.
• Support disaster recovery design, cloud platform, and file services, including recovery tiering with defined RTO and RPO, pilot light versus active-passive trade-offs, non-disruptive failover testing, and divisional cloud accounts.
• Support file-services resilience and legacy distributed file system decommissioning targeting zero RPO and sub-five-minute RTO.

Additional Areas of Focus:

• Active Directory backup and forest recovery: Define, test, and document backup, restore, and forest recovery, including the achievable RTO.
• NTLM decommission path: Define when NTLM can be retired and how remaining NTLM use will be audited.
• Certificate authority recovery posture: Define recovery requirements and establish certificate inventory and expiry alerting.
• Privileged access model for the directory: Address the RBAC transition or document the decision regarding its future state.
• Directory-specific recovery testing: Exercise domain controller and directory recovery as part of resiliency testing.
• Windows image catalogue rationalisation: Review the image catalogue and multi-tenant configuration.
• Group Policy surface: Confirm whether Group Policy is genuinely unused or currently unmanaged.

Requirements:

• Expert-level experience with Active Directory and DNS resilience, including replication topology and health, FSMO roles, DFS-R, NTDS, AD-integrated DNS, and domain controllers.
• Expert-level knowledge of Kerberos authentication, including SPNs, duplicate-SPN failure modes, constrained delegation, AES/RC4 encryption, managed service accounts, group managed service accounts, and reverse DNS dependencies.
• Strong experience with identity integration across Windows and non-Windows environments, including LDAP and single sign-on.
• Expert-level experience with golden image and patch pipelines, including image bake automation, CI-scheduled builds, promotion, deprecation, deregistration, and CVE-driven rebuilds.
• Strong Windows observability and PowerShell experience.
• Strong experience with Infrastructure as Code and configuration management, including OpenTofu and tools such as Chef, Ansible, and Systems Manager.
• Strong understanding of cloud infrastructure, security, data-protection controls, and infrastructure automation.
• Strong experience with PKI and certificate services.
• Strong experience with disaster recovery design, including RTO/RPO, recovery strategies, failover testing, and Windows file services.
• Ability to work as a platform and automation engineer in a code-managed Windows environment rather than relying on traditional Windows administration practices.
• Ability to work independently across complex, business-critical Windows infrastructure and communicate technical decisions clearly.