UK Managed Security Service Provider · Coventry

Sovereign security,
built on open foundations.

We design and operate security systems for organisations that cannot afford to lose control of their data — on open-source foundations you can inspect, host, and own.

Talk to our team How we work

Working with UK central government departments, defence-industrial suppliers, and private clients where discretion is the requirement.

Most security is a black box. That is the risk.

When you cannot inspect a platform, cannot host it where your obligations require, and cannot keep it running without a vendor's permission, you have not reduced risk — you have relocated it, out of your sight and out of your control.

For government, and for anyone holding truly sensitive data, that trade is no longer acceptable.

02 The Cairn approach

Open by design

Software you can audit line by line.

Wazuh · Zabbix · pfSense
Ansible · GLPI

Sovereign by default

Hosted where your law and your risk appetite require. Your data stays yours.

iii

Yours to keep

You can take the platform in-house. Our model doesn't depend on locking you in.

Five capabilities, each on an open foundation.

Managed Detection & Response

24/7 monitoring, detection, triage and response from a UK-based, cleared team. You can read every rule we write.

Built on Wazuh + OpenSearch

Infrastructure Monitoring

Full-estate visibility of availability, performance and capacity — without per-metric licensing deciding what you may see.

Built on Zabbix

Network & Perimeter

Inspectable, self-hostable firewalls, segmentation and secure remote access. A perimeter you can read.

Built on pfSense / OPNsense

Security Engineering & Automation

Hardening and change delivered as version-controlled code, mapped to CIS and STIG benchmarks, over one auditable asset record.

Built on Ansible + GLPI

Advisory & Compliance

Pragmatic governance from people who also run the systems — so the advice is buildable, not theoretical.

Built on NCSC CAF · ISO 27001 · CE+

All services

Auditability is the feature.

Every detection rule we write, every firewall policy, every hardening baseline is a version-controlled artefact you can read and challenge. Assurance stops being a leap of faith and becomes something you can check.

Founded

2020

People

~55

Operations

24/7 UK

Clearance

SC / DV

Open where it's best. Honest where it isn't.

Open source is our default, not our religion. Where it genuinely cannot meet a requirement, we say so and integrate the best alternative — and we document exactly why.

See the technology

Bring us the problem you can't hand to just anyone.

Coventry and London. UK-based, cleared, and used to being asked difficult questions.

Talk to our team

Sovereign security,built on open foundations.