Job Description

We are seeking a hands-on Email Security Engineer to support the delivery and operational uplift of Optus email security. The contractor will work closely with Luc and the Director, Data Protection & Email Security, to strengthen outbound controls, complete Mimecast implementation activities and support the controlled decommissioning of Trend Micro email security capabilities.

This is a delivery-focused role for someone who can operate at both engineering and operational levels — designing changes, implementing them, troubleshooting issues, documenting outcomes and handing over reliable services to BAU teams.

Key responsibilities

- Execute configuration and engineering changes in a controlled manner.
- Coordinate testing with technical teams and business stakeholders.
- Develop runbooks, technical procedures, support models and knowledge-transfer materials.
- Monitor post-change outcomes and recommend further tuning.
- Escalate issues early and drive actions through to completion.
- Design,



implement and validate the Mimecast outbound mail flow.
- Review outbound routing, controls, policies, authentication and delivery behaviour.
- Identify and close gaps across data protection, malware, impersonation, URL and policy enforcement controls.
- Troubleshoot mail-flow issues across Mimecast, Microsoft 365 and downstream or third-party systems.
- Support testing, cutover planning, monitoring and rollback readiness.
- Map current Trend Micro email security capabilities, integrations, dependencies and traffic flows.
- Define the migration and decommissioning sequence in coordination with the Mimecast target state.
- Remove or retire legacy configurations, rules and integrations safely.
- Validate that required protection and mail-flow outcomes remain in place after each change.
- Support defect resolution, rollback planning, evidence capture and final closure of the decommissioning work.

📌 Email Security Engineer - Contract (Sydney)
🏢 NCS Australia
📍 Sydney