Files
hq/03-DESIGN
jschoubben a253afe020 Scenario lifecycle, and how two scenarios coexist
ADR 0032: a scenario is a closed address space. Every segment materialises
as its own isolated link belonging to one instance, so two scenarios raised
from the same declaration hold the same addresses and never meet. The
declaration keeps its literal addresses and they mean what they say —
allocating from a pool would have made them a fiction, so a scenario
reproducing a specific topology would stop reproducing it.

The constraint that follows shapes everything: the lab never reaches into a
scenario over IP. It talks to machines through the virtualisation layer's
own channel. If it reached them by address, the workstation would need a
route into each scenario, and two carrying the same prefix would give it
two routes to one destination — failing not with an error but by one
scenario's traffic arriving in another.

That also makes reachability an honest question. Can this machine reach
that one is asked from INSIDE, by executing on the first, rather than
probed from a workstation that is not on the network and whose opinion
would be a different question with a misleadingly similar answer.

The lifecycle itself: six verbs, of which raise and destroy are enough to
be useful and the rest are what make repetition cheap. Raising is
convergent rather than incremental, because a lab behaving differently
from the thing it tests teaches the wrong habit.

A failed raise leaves the wreckage standing. Tearing down on failure
destroys the only evidence, which is backwards — a scenario that failed to
raise is more interesting than one that succeeded.

Snapshots are whole-scenario. Per-machine would be cheaper and wrong: the
mesh keeps state spanning nodes, so restoring one machine while its peers
move on produces a mesh that has never existed, and faults found there
would be artefacts of the lab.

Closes the declaration's open question about running several scenarios at
once.
2026-08-23 23:53:00 +02:00
..

03-DESIGN

The authoritative specification. Implementation is built against what is written here.

Two layers

Folder What it is
00-as-is/ The mesh that exists today. Shipped behaviour, described as it is — including behaviour nobody would choose again.
01-to-be/ The mesh being built toward. Every statement traceable to a record in 02-DECISIONS/.

They are never mixed. A statement about the future does not belong in an as-is document, and an as-is document is never edited to describe an intention.

When a to-be design ships, it does not move. Its as-is counterpart is written or updated, the to-be document's status becomes implemented, and both stand — one describing what runs, the other recording what was intended. Deleting the intention loses the reasoning, which is the expensive half.

Frontmatter

Every design document (not the READMEs) carries:

---
layer: as-is | to-be
status: designed | in-progress | implemented | abandoned
code: []                 # owning code repo(s), from 00-META/repos.md
updated: YYYY-MM-DD      # date of the last status change, not of text edits
decisions: []            # 02-DECISIONS/ records this document rests on
---

For an as-is document, status: implemented is the normal state — it describes something that runs — and code: names where that implementation lives.

Status changes when implementation state changes, never because design text was edited. An implemented claim must be defensible from the owning repository's main branch, not from intent. If it cannot be checked, it is in-progress.

Cross-cutting views are generated from this frontmatter by the hq-status skill and never written to disk.

What belongs here

Functional analysis, architectural description, and specification — prose and diagrams only, no code. A manifest field may be named; a manifest may not be pasted. A document enters the to-be layer only after the decision behind it is recorded in 02-DECISIONS/ and the research that produced it is closed.

Subfolders are encouraged where a layer grows enough to need them.