Role Summary
Circle Cloud Communications Ltd is a telecommunications provider operating carrier-grade, on-prem infrastructure. We maintain our own IP space via RIPE, run our own ASN, and deliver business-critical unified communications and telephony services. We're also building Olatti, our next-generation business phone system, which runs on the same infrastructure estate.
The Senior DevOps Engineer owns the platform layer of that estate: virtualisation, storage, container orchestration, and the automation that holds it all together. You'll run the infrastructure beneath two products - the established circle.cloud telephony platform and the new Olatti platform - on one shared estate of our own hardware in UK data centres. Keeping data on infrastructure we control is a deliberate choice, and this role is central to it.
This is a hands-on senior engineering role. You'll work alongside the Infrastructure Manager, who owns the network layer, and you'll be the senior authority on everything that runs on top of it: hypervisors, storage clusters, Kubernetes, deployment pipelines, and the monitoring that tells us about problems before customers do.
About the Environment
- On-prem, bare-metal infrastructure across four interconnected sites
- Fibre ring topology with geographic resilience
- Minimal public cloud usage
- Business-critical production telecoms services with real-world uptime demands
- Two product platforms - circle.cloud and Olatti - running on one shared estate
- A small, capable team where senior engineers own their domain end to end
Key Responsibilities
Virtualisation & Compute
- Operate, maintain, and improve our Proxmox VE virtualisation estate across all data centre sites
- Own capacity planning, host lifecycle, and hypervisor upgrades with minimal service impact
- Ensure the compute layer meets the availability demands of real-time communications workloads
Storage
- Own storage architecture, performance, and integrity across the estate, including Ceph and block storage
- Own backup and recovery: replication, retention, and restore procedures that are tested regularly, not assumed to work
- Plan and execute storage growth ahead of demand from both platforms
Container Orchestration
- Run container orchestration in production day to day
- Lead our continued move deeper into Kubernetes: cluster design, workload migration, and operational standards
- Support development teams on both products with reliable build, deployment, and runtime environments
Automation & Infrastructure as Code
- Build and maintain infrastructure as code with Ansible and Terraform - the estate should be reproducible from code, not folklore
- Automate routine operations, patching, and provisioning across both platforms
- Drive configuration consistency across sites and environments
Monitoring, Reliability & Incident Response
- Own monitoring and alerting for the platform layer, keeping signal high and noise low
- Act as senior escalation for platform-level incidents on either product, including out-of-hours escalation on a planned basis
- Contribute to post-incident reviews with clear root cause analysis and corrective actions
- Participate in disaster recovery and failover testing across the estate
Documentation & Collaboration
- Maintain accurate runbooks, diagrams, and SOPs for the platform layer
- Put forward architecture proposals and business cases to the Infrastructure Manager for review and approval
- Collaborate with the network, service, and development teams to align platform work with product needs on both circle.cloud and Olatti
- Get hands-on in the data centre when the work calls for it
Required Experience
- Five or more years in DevOps or infrastructure roles, ideally in SaaS, telecoms, or other infrastructure-heavy environments
- Production Kubernetes experience - designing, running, and debugging real workloads. This is the single biggest win.
- Strong Proxmox experience, especially Ceph and block storage - a close second
- Solid infrastructure-as-code habits with Ansible, Terraform, or similar
- Linux administration at scale, bare metal and virtual
- Experience operating production-critical environments where uptime is non-negotiable
- Strong documentation habits in production environments
- UK-based, within reach of Southampton for office days and data centre visits
Desirable Experience
- Prior experience in a telecoms, VoIP, or UC service provider environment
- Understanding of real-time media workloads (SIP, RTP) and what they demand from infrastructure
- Database operations experience (PostgreSQL or similar) in production
- Networking fundamentals sufficient to work effectively alongside a carrier-grade network team
- CI/CD pipeline design and developer platform experience
Working Style
- Hands-on, methodical, and reliable in live production environments
- Calm, decisive, and accountable under pressure
- Strong ownership mindset - you see problems through to resolution and write down what you learned
- Collaborative with network, service, and development teams
- Comfortable owning a domain end to end in a small senior team
Working Hours & Holiday
Working Hours
08:30 to 17:30. This is a senior role with autonomy and accountability. We value outcomes, ownership, and effective time management over clock-watching. Out-of-hours support is required on a planned and escalation basis.
Holiday
- 21 days annual leave
- Birthday day off
- Bank holidays
Benefits
- Company events
- Company pension
- Office canteen & games zone
- Cycle to work scheme
- Discounted or free food
- Employee discount
- Health & wellbeing programme
- On-site parking
- Private medical insurance
- Referral programme
- Work from home (as part of agreed hybrid pattern)
Job Type: Full-time
Pay: £55,000.00-£75,000.00 per year
Benefits:
- Canteen
- Company pension
- Cycle to work scheme
- On-site parking
- Private medical insurance
- Work from home
Experience:
- Kubernetes: 2 years (required)
- CEPH: 2 years (required)
- Proxmox: 2 years (required)
Willingness to travel:
Work Location: Hybrid remote in Southampton SO14
