The Immutable OS to Operate at Scale.

Kairos vs Others

Kairos combines the operational model of an immutable image-based OS with the openness of a distro-agnostic build system and the ergonomics of Kubernetes-native lifecycle management.

* Yes for CMS because they can manage many distros and apply ongoing config, but they do it by mutating the running host rather than by shipping a new immutable machine image. Puppet and Salt describe keeping systems in a predetermined state by reading actual state and changing the target system in place. Ansible is documented as configuring most operating systems and deploying software, and Red Hat describes it as agentless automation over SSH/APIs.

+ Some image-based systems such as bootc support custom bootable images, but they require adopting the bootc-compatible image model. This is different from reusing an existing distro image pipeline directly under the same assumptions.

^ Support varies by system. Talos supports updating machine configuration on running nodes, and Bottlerocket has a persistent API/settings model. Flatcar and Fedora CoreOS primarily rely on Ignition-style first-boot provisioning rather than the same kind of post-install layered config workflow.

~ Bottlerocket provides Kubernetes-coordinated updates via Brupop, and Talos provides strong day-2 lifecycle operations through talosctl, but these approaches do not generally expose the same breadth of operator-driven OS lifecycle management through Kubernetes resources as Kairos.

# Some SPOS offer different prebuilt variants or orchestrator targets, but that is not the same as choosing which Kubernetes distribution to run on the same operating system model. Bottlerocket, for example, ships environment-specific variants rather than a bring-your-own Kubernetes distro approach.