Location
Hybrid working based at any of our Core HQs in Birmingham, Leeds, Liverpool or London (Canary Wharf). As a hybrid worker, you will be expected to spend a minimum of 60% of your contractual working hours (approximately 3 days a week pro rata, averaged over a month) on-site. Our core HQ offices are modern and newly refurbished with excellent city centre transport links and benefit from co-location with other government departments such as the Department for Health and Social Care.

Hours
Full time, with participation in on-call and out-of-hours services as required.

Salary
£56,185 - £70,566 per year, plus a market pay supplement of £6,650 per annum (to be reviewed in February 2027).

About the Role
The Senior Specialist Engineer – Networks is a senior technical role responsible for delivering and maintaining excellence across the network infrastructure estate at the UK Health Security Agency (UKHSA). You will act as a subject matter expert and network architect, driving the design and evolution of the network environment, providing expert-level technical leadership during major incidents, and working across multi-disciplinary teams to ensure network services underpin the organisation's operational and scientific mission.
Working alongside the Network Manager, you will ensure all systems are optimally configured, resilient, secure, and performant. You will own and maintain comprehensive network architecture documentation including High Level Designs (HLD), Low Level Designs (LLD), topology diagrams, and As-Built records.
The role includes leading the design, implementation, and lifecycle management of resilient, scalable, and secure LAN, WAN, WLAN, and cloud-connected infrastructure aligned with NCSC Secure by Design principles. You will provide technical assurance across estate modernisation, science campus, data centre, and hybrid cloud programmes.
As a senior technical authority, you will lead network security and operational resilience efforts, administer key security technologies such as Palo Alto NGFW, Panorama, VPN, micro-segmentation, DMZ, and Zero Trust architectures, and act as the primary network technical authority during major incidents.
You will also drive network automation and Infrastructure as Code using tools such as Ansible and Python, manage vendor relationships, procurement planning, and proof-of-concept evaluations. Your role includes producing technical documentation, supporting ITIL processes, mentoring engineers, and delivering high-quality customer support.
This role is critical to UKHSA’s mission to prevent, prepare for, and respond to infectious diseases and environmental hazards, ensuring the safety and health security of communities across the UK.

Experience
- Substantial experience in a senior network engineering role with advanced knowledge of enterprise routing and switching, network security, wireless technologies, and large-scale network infrastructure management.
- Proven experience producing and maintaining network architecture artefacts including High Level Designs (HLDs), Low Level Designs (LLDs), topology diagrams, reference architectures, and As-Built documentation.
- Demonstrable ability to lead or contribute to network architecture initiatives, provide technical assurance and design reviews, and ensure solutions align with organisational standards and security-by-design principles.
- Significant experience acting as a senior technical authority during major incidents, leading diagnosis and resolution activities within multi-disciplinary Major Incident Response Teams.
- Experience producing Root Cause Analysis (RCA) reports, Post-Incident Reviews (PIRs), and maintaining incident runbooks and escalation procedures.
- Skilled in monitoring network infrastructure to optimise performance, support capacity planning, identify risks, and maintain service availability and resilience.
- Excellent written, verbal, reporting, and presentation skills with the ability to communicate complex technical concepts to both technical and non-technical audiences.

About you
- Strong leadership skills with the ability to influence and persuade across organisational boundaries.
- Ability to work effectively under pressure and manage competing priorities.
- Collaborative team player with a commitment to delivering outstanding customer service.
- Enthusiastic about continuous service improvement and innovation.

Qualifications
- Formal technical qualification equivalent to CCNP level or above, or substantial equivalent experience.
- Desirable experience includes:
- Network Function Virtualisation (NFV) and Software Defined Networking (SDN) architectures.
- Advanced network automation toolchains such as Terraform, Ansible, or Python-based frameworks.
- Hands-on experience with SIEM platforms (e.g. Splunk, Microsoft Sentinel) for network security monitoring.
- Experience with Zero Trust technologies such as Zscaler ZIA/ZPA, Illumio, or equivalent.
- Familiarity with network observability tools like ThousandEyes, NetBrain, or Datadog.
- Experience with ITSM platforms (e.g. ServiceNow) including major incident management.
- Familiarity with HPC or scientific network environments.
- Ability to communicate complex matters and handle difficult situations requiring persuasion and influence.