Skip to main content

ADR 0014: Platform base ownership and support tiers

Status: accepted (2026-10-15)

Context​

ADR 0004 requires each workstation to compile Core onto its platform's official bootc base, so a RHEL workstation is RHEL, not a derivative. That rule has no answer for a platform whose vendor publishes no bootc base: Canonical publishes ubuntu OCI container images, not bootc operating systems, and the only available bases are community recipes. The one exercised in the 2026-10-15 spike failed to build at HEAD, destroyed the /var skeleton snapd and apparmor install into, and shipped Flatpak 1.16.6 without flatpak preinstall. Read strictly, ADR 0004 says Ubuntu is unsupported; an organization may still own the base.

Decision​

  1. The official-base rule stands wherever an official base exists. A RHEL workstation still starts from registry.redhat.io/rhel10/rhel-bootc, and RHEL-derived images are still never published or redistributed.
  2. A platform with no vendor base may be added only as an organization-owned base, and only with all of:
    • A named owner: a person or team accountable for the base, its fixes and its updates, recorded in the Platform resource. An unnamed owner is not a tier; it is an omission.
    • Recorded provenance: the upstream recipe and its pinned commit, its license, and every local change with the measured reason for it.
    • A declared support tier, for example vendor or organization; a tier of organization must be visible wherever the platform is described and must never be presented as vendor support.
    • Bounded validation claims: what was verified, how, and what was not (invariant 10). "Builds and boots" is not "supported".
    • A maintenance policy: who moves the pins (base digest, bootc commit, package set), how quickly, and who responds when an update breaks a workstation.
  3. The base lives in its own repository. Its recipe, pins and provenance are reviewed there; this repository consumes a base reference and the tier its owner declared.
  4. This changes no compiler behaviour. Adding a platform is still adding a Platform resource (ADR 0004), and this ADR introduces no kind.

Consequences​

  • Ubuntu becomes expressible as a platform without pretending that Canonical supports the result. An owned base is an owned liability, and the Platform resource names who carries it.
  • A base whose owner is unnamed cannot be added. "We will figure it out later" is not a support tier.
  • The rule that protects RHEL is untouched, because it is stated as the general case rather than as a RHEL exception.
  • Out of scope here: which software and look choices belong to a platform or an organization. resources/desktop/deskos-core.yaml sets no dock.enabled, wallpaper, login logo or favorites (the look comes from the deskos-look profile), and resources/software/deskos-core.yaml carries the package set without the desktop choices. Composition offers no removal (ADR 0003), so anything Core chose could not be subtracted by an organization.