Senior Systems Engineer
Build the systems that power connectivity at national scale
At AllPoints Fibre Networks (APFN), we’re transforming how the UK connects. As a full‑fibre network wholesaler, we make high‑speed broadband simple, scalable and accessible through our API‑driven platform, Aquila.
We’re looking for a Senior Systems Engineer to join our Platforms Engineering team, playing a key role in the design, operation and continuous improvement of our Linux platforms, virtualised infrastructure, and hybrid cloud integrations.
This is a hands-on senior role focused on engineering reliable systems, solving complex problems, and supporting the evolution of our infrastructure, while mentoring others and contributing to strong engineering practices.
What you’ll be doing
Systems & Platform Engineering
Engineer, operate and improve Linux-based platforms supporting internal services and ISP-facing systems
Own and support our Proxmox virtualisation environment, with VMware as a legacy footprint
Build and maintain highly available, resilient infrastructure with a focus on performance and stability
Troubleshoot complex system issues across compute, storage and networking layers
Support and enhance shared lab environments to enable testing, development and consistent builds
Hybrid Infrastructure & Integration
Build and maintain secure connectivity between on-prem systems and AWS
Support AWS services including networking, identity and service integration
Ensure monitoring, alerting and visibility across hybrid infrastructure
Assist with service transitions, operational readiness and capacity planning
Automation & Operational Excellence
Develop and deliver automation using Python, Terraform and Ansible
Improve system reliability and consistency through Infrastructure as Code and repeatable processes
Maintain and enhance monitoring using Prometheus, Grafana, Zabbix, LibreNMS, ELK and Graylog
Ensure backup, recovery and resilience processes are implemented and regularly tested
Promote strong standards across documentation, build quality and operational practices
Technical Ownership & Leadership
Act as a senior escalation point for complex technical issues
Take ownership of problems through to resolution, driving root cause analysis and improvements
Mentor and support engineers, particularly across Linux, automation and systems troubleshooting
Contribute to technical design discussions and platform improvements
Produce clear documentation (HLDs/LLDs) and share knowledge across teams
On-call & Reliability
Participate in an on-call rota, supporting incident response and service recovery
Focus on preventative engineering and continuous improvement following incidents
What you’ll bring
Essential experience
Strong, hands-on expertise in Linux system administration and troubleshooting
Experience with Proxmox, KVM/QEMU or similar virtualisation technologies
Proven ability to diagnose and resolve complex infrastructure issues
Experience with automation and scripting (Python preferred)
Knowledge of Infrastructure as Code (Terraform) and configuration management (Ansible)
Solid understanding of networking fundamentals and system integration
Experience supporting monitoring and observability platforms
Ability to take ownership and operate effectively in a senior engineering capacity
Strong communication skills with the ability to document and explain technical solutions
Nice to have
AWS experience (VPCs, IAM, hybrid connectivity, high availability design)
Experience with ISP-related systems (e.g. Kea DHCP, FreeRADIUS, MariaDB, ELK, LibreNMS)
Knowledge of routing protocols (BGP, OSPF)
Experience with hybrid networking (VPNs, Direct Connect)
Exposure to lab or test environment design
Relevant certifications (AWS, Linux, networking, automation)
Familiarity with XGS‑PON technologies
Why join APFN?
We believe great engineering starts with well-supported people. Our benefits include:
30 days’ annual leave (plus bank holidays)
Private medical & dental cover
Income protection & life insurance
Health and wellbeing support
Pension and additional benefits
A strong commitment to learning, development and inclusion
About us
At APFN, we’re curious, ambitious and delivery-focused. We move fast, support each other, and take pride in building reliable systems that make connectivity simpler for our partners.
If you want to work on meaningful infrastructure at scale — we’d love to hear from you.
👉 If you don’t meet every requirement but are excited by the role, we still encourage you to apply.