Files
hq/03-DESIGN/01-to-be
jschoubben 5b3d0ebd4f ADR 0046 — the installer fetches what it pins
The blocking question was where a container image comes from, and the version
that blocked assumed the machine might have no network. That assumption came
from the LAB: a scenario is a closed address space by design, which is what lets
two scenarios hold the same addresses without meeting. Production is not sealed
— a machine being adopted has a network, and one that does not is a machine
where very little works anyway.

So substrate.lock carries references, not payload: an image name and a digest,
fetched at apply time. A first node pulls from upstream because no mesh registry
exists yet; every node after that pulls from the mesh's own. The lab is the
exception and places images itself, the way it already places the host binary —
a property of a test environment, and letting it dictate the production design
would be the tail wagging the dog.

Pinned by DIGEST rather than tag. Reproducibility comes from pinning the
identity of a thing, not from carrying its bytes, which is what makes fetching
acceptable rather than a compromise.

ADR 0041 survives untouched, which was the point. "Copy it onto a machine and
run it" stays literally true — one binary, a few megabytes, which then fetches
what it was told to. Carrying images would have quietly redefined the property
that decision rests on.

Costs accepted and named: an apply can now fail because something is
unreachable, which a self-contained artifact could not, so it must fail legibly
— naming what it could not fetch and from where. And the lab needs a way to
place images into a machine that also has no container runtime, both of which
are lab-installation concerns and neither solved here.

Research 012's build-time-versus-apply-time reframing narrows accordingly: it
still holds for what a tailored installer contains, and no longer has to hold
for images.
2026-08-26 23:52:46 +02:00
..

03-DESIGN / 01-to-be

The mesh being built toward. Every statement here traces to a record in 02-DECISIONS/; nothing arrives by drafting.

A document here describes an intention. What currently runs is in 00-as-is/, and the two are never merged — when something ships, the as-is document is written and this one's status becomes implemented.

Document Covers Rests on
00-work-breakdown.md How the decomposition gets built, in what order, and where a human must look ADR 0015
01-end-to-end-testing.md The lab: a real mesh a change can be run against before it reaches nodes ADR 0016, 0029
02-scenario-declaration.md What a scenario declares — the underlay, and what to place on it ADR 0031
03-scenario-lifecycle.md What happens to a scenario — raise, snapshot, restore, move, destroy ADR 0032
04-lab-installation.md Getting the lab onto a clean machine, and why it verifies capability rather than installation ADR 0008
05-the-node-host.md Tier 0 — the one thing installed by hand, and the only thing that changes a machine ADR 0037
06-the-control-plane.md Tier 2 — what the term means, and the test for what belongs in it ADR 0037
07-the-substrate.md Tier 1 — what the control plane consumes and cannot grant itself ADR 0038

Not yet written

  • The eight bounded contexts. ADR 0015 decides the decomposition; the per-context specifications do not exist yet. The work breakdown says in what order they are needed.
  • Domain grouping outside the core. ADR 0017 settles the principle and explicitly does not settle the domain list. That is a research effort, not a design document, until it concludes.