Files
hq/02-DECISIONS/README.md
T
jschoubben 10fa7c76d7 The substrate is a store and a broker
Third correction to one table today, found the same way as the other
two: by asking whether both halves of the test were answered, or only
the easy one.

0006 admits the registry because "it cannot grant itself a repository" —
true, and the second half. Nothing established that the control plane
needs one in order to run. Counted rather than argued: the bundle raises
twelve resources and no registry is among them. The registry arrives
afterwards as an ordinary module, which is exactly what the lab asserts.

0006 half-said this already, calling it "substrate by role and ordinary
by delivery, provisioned once there is a control plane to do it". A
member provisioned by the thing it supposedly precedes is not a member;
that phrase was carrying a contradiction rather than resolving one.

The registry is a closer call than the object store and the difference
is worth keeping: the control plane never touches an object store at
all, but it genuinely uses the registry. So the registry is a real
dependency of the mesh operating and not of the control plane starting —
and it is the second that the word means.

The substrate is now exactly what the bundle raises, which is the
strongest form the list can take: checkable by counting rather than by
reading an argument, and the two cannot drift.

The finding is not about substrates. A test with two conditions is a
test only when both are asked.
2026-08-31 20:30:19 +02:00

7.1 KiB
Raw Blame History

02-DECISIONS

Architecture decision records — the "why" trail behind the rules in 00-META and the specifications in 03-DESIGN.

Numbered 02 because a decision precedes the design it authorises. Research concludes, the decision is recorded here, and only then is the design written. Following the folder numbers walks the process in the order it happens.

One file per decision, numbered, never deleted. A superseded record has its status: changed and gains a pointer to what replaced it — its text is never edited. The reasoning that was rejected is the expensive half to rediscover.

The records run in the order the decisions were taken, oldest first.

Every decision is a record. There is no ledger and no index file — if a decision is worth recording it is worth a record, and if it is not worth a record it is not recorded (ADR 0019). A "decision" small enough to be one line is almost always a rule, and a rule belongs in 00-META/how-we-build.md, where it is enforced and keeps the incident that earned it.

Frontmatter

---
status: proposed | accepted | superseded
date: YYYY-MM-DD          # when the decision was taken, not when it was written down
deciders: name
reconstructed: true|false # true when the record was written after the fact from evidence
superseded-by:            # 02-DECISIONS/NNNN-....md, when status is superseded
extends:                  # 02-DECISIONS/NNNN-....md, when this record widens an earlier one
---

Body

# N. Title in plain language

## Context            what was true, with evidence
## Considered Options numbered, each with why it was rejected
## Decision           what was decided
## Consequences       what follows, including what got harder
## References         commits, pull requests, knowledge-base entries, prior art

State evidence, not assertion. "Zero of 124 modules declare brain as a dependency" outranks "the dependency rule is not followed".

Reconstructed records

Records 0001–0014 were written on 2026-08-23, after the decisions they describe. Records 0015 onward were taken as records. Those decisions were taken in implementation rather than in a document; the records state what was decided and the evidence it was decided from, and each carries reconstructed: true and says so in its first lines.

A reconstructed record is not a transcript. Where the deliberation is not recoverable, the options section states what the alternatives were and why the chosen one won on the evidence available — not a discussion that did not happen. Where a date is not establishable it says so rather than guessing.

Index

A number identifies a record and never changes. Records are referenced from outside this repository — code comments, commit messages — so a number that moves invalidates them silently. Renumbering once cost 96 references across two code repositories, and that is why the numbers are now fixed.

So the folder is in creation order, and the reading order lives here. It is generated from each record's topic: and written, because a reader looking at the folder on a forge sees the folder rather than a command. The objection to a written index is that it drifts — which is answered by checking it rather than by refusing to write one:

python3 00-META/checks/index.py --write    regenerate
python3 00-META/checks/index.py            fail if stale

What the mesh is

Its tiers, from the bottom up

What runs on them, and how it gets there

How it is built

How it is checked

How we work