Files
hq/02-DECISIONS
jschoubben e1ad39b500 Per-OS hosts, and an init asked for only start and restart
0060 -- the host is built per operating system. systemd and pacman are the Arch
host's implementation, not abstractions the mesh has to grow. They are not
independent choices: a machine has pacman because it is Arch, and the package
manager, service manager and packaging format arrive together as one decision
somebody made at install time.

Rejected abstracting them, and the reason is correctness rather than effort.
The service applier reads LoadState to tell "not installed" apart from
"stopped", which is what stops it reporting absence as success. An interface
spanning systemd and OpenRC degrades to what both express, and the lowest
common denominator is exactly where that fault lives.

Almost all of it is shared -- the vocabulary, store, apply loop, read-back
discipline, refusal model, bundle and link are portable. Two appliers differ.
And delivery was already per-OS, since a .pkg.tar.zst is an Arch artifact, so
this is the seam that already existed.

Android is the interesting case rather than Debian: no service manager, no
package installation, usually no root. Such a host implements file, directory
and action and refuses the rest -- the same refusal a host already gives an
unknown type, with a different reason. Those three are the portable floor.

The container runtime is deliberately left open: it is not an OS split, since
Arch runs docker or podman.

0061 -- the init is asked for start-at-boot and restart-on-exit, and nothing
else. Both are expressible in OpenRC, runit, s6 and an Android init.rc.
Counting failed starts and rolling back moves into a launcher, because that is
the one piece which must work when the host does not, and a script with a
counter can be tested where OnFailure= can only be hoped for. Supersedes 0059,
keeping its reasoning in full.

The checker found all six places citing 0059 and refused the commit until they
named the replacement.
2026-08-27 23:46:11 +02:00
..

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 A superseded record has its status: changed and gains a pointer to what replaced it — its text is never edited.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 0026). 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

The index is generated, not maintained — run the hq-status skill, which reads the frontmatter of every record. A hand-written index drifts from the folder it describes, and this one had already done so after a single addition.