Files
hq/03-DESIGN/01-to-be
jschoubben cbcbba8099 A provision names its engine; the substrate supplies only the control plane
**0027 — provisions.** A module written against PostgreSQL could be
matched to a provider of SQL Server, resolve as satisfied, and fail on
its first query. The name said the role, so nothing distinguished
engines. Refusing on ambiguity could not help: with one provider of
each name nothing is ambiguous. Enforced at parse rather than
documented, because the old naming was the documentation.

**0028 — the substrate.** 0006 admits an object store on the grounds
that it cannot grant itself a bucket. That answers the second half of
the test and assumes the first: the control plane does not need one.
Verified — no S3 client in mesh-control, and internal/builder/registry.go
records the deliberate choice to put artifacts in the OCI registry as
content-addressed blobs. The row was inherited from the system being
replaced, where an object store distributed module tarballs, and was
never re-tested against the definition above it.

So an object store is an ordinary module, and a mesh with nothing
needing one runs none. Migrating it is module work, not substrate work.

0028 also states what 0006 left unsaid: a substrate service and a
module of the same product are different instances. The substrate is
raised from the bundle before any mesh exists, so it is not in the
module graph — a workload depending on it would depend on something the
graph cannot see, cannot rotate a credential for, and cannot move, and
would put workload data in the store the control plane keeps its own
state in.

Both records were found by reading code against design rather than
design against itself, which is the review that should have happened
sooner.
2026-08-31 17:13:07 +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 0001
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 0016
03-scenario-lifecycle.md What happens to a scenario — raise, snapshot, restore, move, destroy ADR 0016
04-lab-installation.md Getting the lab onto a clean machine, and why it verifies capability rather than installation ADR 0010
05-the-node-host.md Tier 0 — the one thing installed by hand, and the only thing that changes a machine ADR 0005
06-the-control-plane.md Tier 2 — what the term means, and the test for what belongs in it ADR 0005
07-the-substrate.md Tier 1 — what the control plane consumes and cannot grant itself ADR 0004, 0048
08-connectivity.md One context in full — overlay, resolution, exposure, filtering, certificates ADR 0007, 0050, 0051, 0055
09-the-node-lifecycle.md How a machine becomes a node, stays one, and stops being one ADR 0004, 0051
10-delivery.md Modules, the three edges, and how a change becomes a running thing ADR 0010, 0064, 0065
11-a-board.md What a person sees of the mesh, and why it is read from what runs ADR 0008, ADR 0001
12-a-module-repository.md A module repository, and what builds it ADR 0009, ADR 0010, ADR 0005
13-credentials-and-their-rotation.md Credentials, and moving them without a consumer holding one the provider does not know about ADR 0001, ADR 0009
14-model-access.md Model access as a provision, and what a licence is bound to ADR 0024, ADR 0009
15-the-agent-session.md One mechanism started twice — a node's session and the mesh's ADR 0004, ADR 0026

Not yet written

  • The remaining six contexts. ADR 0006 settles the list at seven; connectivity is the first written in full (08) and the other six do not exist yet. The work breakdown says in what order they are needed.
  • Domain grouping outside the core. Not needed. ADR 0009 is superseded by ADR 0009: there is no domain module to group into, so there is no domain list to settle. Relationships are edges, and grouping is a tag and a query.