The Senior Systems Engineer is responsible for the design, implementation, and ongoing maintenance of enterprise server environments across both Windows and Linux platforms in equal measure. The role requires deep, hands-on technical expertise in both operating system, ensuring infrastructure is secure, highly available, and aligned with business and government compliance requirements.
Working across hybrid on-premises and cloud environments, the Senior Systems Engineer manages complex build, migration, and upgrade activities across the Windows and Linux environments, and resolves incidents and problems on both platforms. They act as a senior technical authority on Windows and Linux operating system architecture, patching, hardening, and lifecycle management, and contribute to architecture decisions, capacity planning, and continuous service improvement.
Key responsibilities
* Design, build, and maintain Windows environments (Workstation and Server, including Active Directory, Group Policy, DNS, DHCP, certificate services, and Proxmox) and Linux server environments (RHEL, Ubuntu, Debian, or equivalent), including virtualised and containerised workloads on both platforms.
* Provide ongoing day-to-day administration, monitoring, and optimisation of both Windows and Linux systems.
* Administer and optimise virtualisation and cloud platforms such as Proxmox, Azure, and AWS, including migration of Windows and Linux workloads between on-premises and cloud.
* Implement and maintain system hardening, patching, vulnerability remediation, and configuration baselines on both Windows and Linux, aligned with the ACSC Essential Eight and Information Security Manual (ISM).
* Manage backup, replication, disaster recovery, and business continuity solutions across the Windows and Linux estate, and lead testing of recovery procedures.
* Automate provisioning, configuration, and routine operations across both platforms using PowerShell, Bash, Ansible, or similar tooling.
* Investigate and resolve complex performance, availability, and security incidents on Windows and Linux systems, providing third-level support and root cause analysis.
* Contribute to architecture, design documentation, change records and maintaining current accurate documentation.
Skills and experience
* Significant experience (ideally 10+ years) administering enterprise Windows Server and Linux environments in Production, with demonstrated ability to operate as a primary engineer on both rather than specialising in one.
* Strong working knowledge of Active Directory, identity and access management, Group Policy, PKI, and Microsoft 365 integration.
* Solid Linux administration skills including system management, networking, storage (LVM), package management, SSH, and shell scripting.
* Hands-on experience with virtualisation (Proxmox), storage (SAN/NAS), and enterprise backup tooling supporting mixed Windows and Linux workloads.
* Experience with at least one major cloud platform (Azure preferred, AWS) and infrastructure-as-code practices.
* Strong scripting and automation skills in both PowerShell and Bash (Python or Ansible an advantage).
* Familiarity with monitoring and observability tools (e.g. SCOM, Zabbix, Nagios, Grafana, Splunk) across heterogeneous environments.
* Understanding of the ACSC Essential Eight, ISM, and PSPF controls, and experience operating in accredited or PROTECTED environments.
* Excellent troubleshooting, documentation, and stakeholder communication skills.
Personal attributes
* A positive, can-do attitude with a collaborative and solutions-focused mindset, and a genuine willingness to pitch in and help the team succeed.
* Genuinely enjoys working directly with clients, building strong working relationships, and translating technical concepts into clear, business-friendly language.
* Professional, approachable, and customer-focused, with the patience and empathy to support clients through complex technical issues.
* Takes ownership of outcomes, follows through on commitments, and represents the organisation well in client-facing settings.
Desirable skills
* Solid networking fundamentals including TCP/IP, routing, switching, VLANs, VPNs, and DNS, with the ability to troubleshoot connectivity issues across the Windows and Linux estate.
* Hands-on experience configuring and supporting enterprise networking equipment (e.g. Cisco, Juniper, or equivalent), firewalls, and load balancers.
* Familiarity with network security concepts such as segmentation, micro-segmentation, ACLs, IDS/IPS, and zero-trust principles.
* Exposure to software-defined networking and cloud networking constructs (e.g. Azure VNets, AWS VPCs, NSGs, security groups, ExpressRoute, or Direct Connect).
Clearance
* Experience supporting Australian Government clients and holding a current NV1 clearance or greater.