Merge pull request 'ADR 0142: the mesh delivers its own components as binaries' (#175) from decision/0142-mesh-delivers-its-own-components into main

Measured: the host is a binary somebody copied to four machines, owned by no
package and built by nothing, while the controller, catalogue, builder and vault
are container images publishing no ports at all. Same language, same project,
same kind of work, delivered two ways — and the difference is not a judgement
about either, it is that images are the only delivery that works.

What it costs: genesis must raise a container runtime before the control plane
can exist; updating the control plane goes through a registry the control plane
runs; a host change cannot be rolled out at all; and compiling the language the
mesh is written in is not a capability of the builder, so the controller is built
from a hand-written Dockerfile — the incantation the bundle toolchain exists to
abolish.

Third-party software stays a container: the store, the registry, the broker are
somebody else's build. The container runtime stays on the machine for modules.
What changes is that the control plane no longer needs it to exist.

The receiving half is already built and tested (ADR 0141). Staged: compile Go, an
artifact names its target, deliver a binary, the host first, then the rest, genesis
last.

00-META/checks/records.py

@@ -164,6 +164,12 @@ def check_rests_on(failures, records):
                 # decision is exactly what as-is is for."
                 if rel(path).startswith("03-DESIGN/00-as-is/"):
                     continue
+                # A withdrawn record's citations are history. It instructs nobody -- every reader
+                # is sent to its superseder -- so what it was built on may itself be withdrawn.
+                # Refusing that would mean rewriting the lineage of a record whose reasoning is
+                # the thing the immutability rule protects.
+                if frontmatter(read(path)).get("status") == "superseded":
+                    continue
                 # An extension that supersedes legitimately names what it replaced.
                 this = ADR_FILE.match(os.path.basename(path))
                 supersedes = records[number]["front"].get("superseded-by", "")
@@ -241,13 +247,20 @@ def check_supersession_symmetry(failures, records):
             failures.add("supersession", rel(record["path"]), f"superseder does not exist: {by}")
             continue
         other = records[match.group(1)]
-        claims = os.path.basename(str(other["front"].get("supersedes", "")))
-        if claims != record["name"]:
+        # `supersedes:` may name one record or several. One decision replacing two is a real
+        # situation -- two records that built and refined the same wrong mechanism are withdrawn
+        # by the one record that removes it -- and a check that allows only one would force
+        # either a chain of pro-forma records or an unmarked supersession.
+        claimed = other["front"].get("supersedes", "")
+        if isinstance(claimed, str):
+            claimed = [claimed] if claimed else []
+        claims = [os.path.basename(str(entry)) for entry in claimed]
+        if record["name"] not in claims:
             failures.add(
                 "supersession",
                 rel(other["path"]),
                 f"ADR {number} says this supersedes it; this record does not say so "
-                f"(supersedes: {claims or 'absent'})",
+                f"(supersedes: {', '.join(claims) or 'absent'})",
             )
 
 
@@ -299,8 +312,13 @@ def check_progressive_insights(failures, records):
     unmarked change stands out as the anomaly it is.
     """
     phrase = re.compile(r"progressive insight", re.I)
-    marker = re.compile(r"\*\*Progressive insights?\s*[\u2014\u2013-]\s*(\d{4}-\d{2}-\d{2})\.?\*\*")
-    loose = re.compile(r"\*\*[^*]*[Pp]rogressive insights?[^*]*\*\*")
+    # Both patterns stay on one line: a bold run does not span paragraphs, and `[^*]*` across
+    # newlines will happily join an unrelated `**` far above to the marker below, reporting the
+    # whole span between them. It did exactly that the first time this ran.
+    # Trailing words after the date are allowed — "— 2026-09-26, correcting the one above." — so
+    # an insight can say what it relates to. Only the date's presence and position are fixed.
+    marker = re.compile(r"\*\*Progressive insights?[ \t]*[\u2014\u2013-][ \t]*(\d{4}-\d{2}-\d{2})[^*\n]*\*\*")
+    loose = re.compile(r"\*\*[^*\n]*[Pp]rogressive insights?[^*\n]*\*\*")
     iso = re.compile(r"^\d{4}-\d{2}-\d{2}$")
 
     for number, record in sorted(records.items()):
@@ -313,6 +331,10 @@ def check_progressive_insights(failures, records):
         for m in loose.finditer(text):
             if any(s <= m.start() and m.end() <= e for s, e, _ in good):
                 continue
+            # A bold run carrying a link is discussing an insight — usually another record's —
+            # rather than marking one. A marker never needs to cite anything.
+            if "](" in m.group(0):
+                continue
             failures.add("insights", rel(record["path"]),
                          "a progressive insight is not in the dated marked form "
                          "'**Progressive insight \u2014 YYYY-MM-DD.**': %s" % m.group(0))
@@ -328,7 +350,15 @@ def check_progressive_insights(failures, records):
             if any(s <= m.start() and m.end() <= e for s, e in covered):
                 continue
             line = text.rfind("\n", 0, m.start()) + 1
-            if text[line:m.start()].lstrip().startswith("#"):
+            end = text.find("\n", m.end())
+            whole = text[line:end if end != -1 else len(text)]
+            if whole.lstrip().startswith("#"):
+                continue
+            # A line that also carries a link is discussing the rule, not marking a correction:
+            # a marker never needs to cite anything, and a record that reasons about the policy
+            # must be able to name it. Bare prose with no citation is the informal marking this
+            # is here to catch.
+            if "](" in whole:
                 continue
             if loose.search(text, line, text.find("\n", m.end()) + 1 or len(text)):
                 continue

00-META/glossary.md

@@ -31,8 +31,22 @@ another — and a mesh you cannot name precisely is a mesh two people describe d
 - **store** — the one postgres server. It holds the controller's own context databases
   (`inventory`, `identity`, `licences` — a context owns its store, [ADR 0008](../02-DECISIONS/0008-a-context-owns-its-store.md))
   and every module's own database. One server, many databases — never one shared "mesh database".
-- **broker** — the one lavinmq message bus. It carries the mesh bus on the `/` vhost and a vhost per
-  consumer that requires `amqp`.
+- **bus** — the mesh's own nervous system: NATS, one per mesh, carrying every link the mesh has —
+  control, declarations, builds, events, tool calls
+  ([ADR 0106](../02-DECISIONS/0106-the-bus-is-nats.md)). A module reaches it by requiring
+  `mesh-bus` ([ADR 0128](../02-DECISIONS/0128-the-mesh-bus-is-required-not-ambient.md)); one that
+  does not require it has no account on it. Held by the `mesh-broker` seat, which is named after
+  the *role* rather than the server, so the server can change without the seat doing so.
+- **the deprecated broker** — the lavinmq module. It was the mesh's bus and is not any more. It
+  keeps running as an **ordinary provider** of the `amqp` provision, for modules that need a
+  message broker of their own the way something needs a database
+  ([ADR 0127](../02-DECISIONS/0127-amqp-is-a-provision-not-the-bus.md) (superseded by [ADR 0131](../02-DECISIONS/0131-everything-on-the-mesh-speaks-to-the-broker-seat.md))) — no seat, not foundation,
+  never raised at genesis, and a mesh that never installs it is complete.
+
+  Say *the deprecated broker*, not "the compatibility broker" (it serves the mesh's own modules,
+  not only the predecessor's) and not "the AMQP broker" (naming it after a protocol invites
+  describing the bus by contrast with it, which is backwards: the bus is the mesh's nervous
+  system and this is a module).
 
 ## What the mesh stores and serves
 
@@ -47,7 +61,7 @@ another — and a mesh you cannot name precisely is a mesh two people describe d
 - **seat** — a named role at a scope (node / site / mesh), held by a module assignment, from a
   **closed set** the mesh defines: a claim naming a seat outside the set is refused. A seat may
   **deliver a provision**, and its holder is then the mesh's answer for it when several modules
-  provide it ([ADR 0110](../02-DECISIONS/0110-a-seat-is-a-module-assignment-from-a-closed-set.md)).
+  provide it ([ADR 0126](../02-DECISIONS/0126-a-module-declares-its-own-seats.md) (superseding [ADR 0110](../02-DECISIONS/0110-a-seat-is-a-module-assignment-from-a-closed-set.md))).
   The set, with who holds each seat, is the overview of what a mesh has
   ([26 — The seats](../03-DESIGN/01-to-be/26-the-seats.md)). A seat has a **capacity**: a
   capacity-1 seat is exclusive (one holder); a higher-capacity seat is a **bench** (several holders

02-DECISIONS/0041-events-are-a-relationship.md

@@ -76,6 +76,22 @@ three relationships, one broker, one runtime, all declared on the manifest.
 - The runtime must dispatch a module's event handlers as well as its tools; that generalisation is
   small (both arrive by importing the module's entrypoint) but it is real work.
 
+## Progressive insight
+
+> **Progressive insight — 2026-09-26.** *"No provisioner and no per-consumer setup" was a fact
+> about the transport, and the transport changed.* This record's table says an event's machinery is
+> "nothing but the broker's topic routing", and the text that an event needs "no per-consumer setup
+> — only a subscription". That was true of a topic exchange, where a binding cost nothing and the
+> broker fanned out. On NATS
+> ([ADR 0106](0106-the-bus-is-nats.md)) a subscription is a **durable consumer**: a real object
+> with a name, an ack policy, a delivery limit and its own ack subject, created when a module is
+> assigned and removed when it is not. Per-consumer setup exists, and the controller does it.
+>
+> The decision is untouched — events are declared on both sides, 1:many, credential-free, and
+> still provisioning's lighter sibling; the lightness is now relative rather than absolute.
+> [ADR 0126](0126-a-module-declares-its-own-seats.md) adds the relationship this record's two
+> columns had no room for: work addressed to a role, where exactly one holder must act.
+
 ## References
 
 - [ADR 0002](0002-nodes-communicate-over-a-broker.md) — the broker events ride.

02-DECISIONS/0106-the-bus-is-nats.md

@@ -75,6 +75,30 @@ after its deliveries are exhausted; a module's account cannot publish outside it
 subscribe outside its `consumes`. Then the cutover bed: a mesh on AMQP with the predecessor's
 compatibility broker beside it moves its bus in one rollout with every node reporting afterwards.
 
+## Progressive insight
+
+> **Progressive insight — 2026-09-26.** *The compatibility broker was not single-purpose when this
+> was written.* This record says the adopted AMQP broker is "kept as a module with one purpose —
+> the predecessor's clients". Two modules of the new mesh also depended on it, through a `requires:
+> ["amqp"]` grant its provisioner answered with a private vhost — `amqp-ping` and
+> `amqp-email-forwarder`. On the retirement condition below, both would have been left requiring
+> something no provider answers.
+> [ADR 0125](0125-the-bus-is-the-only-broker.md) resolves it by moving them onto the bus and
+> retiring the interface, which makes this record's sentence true rather than merely intended. The
+> decision — the bus is NATS, the AMQP broker becomes the predecessor's compatibility broker and
+> retires with the last of them — is unchanged.
+
+> **Progressive insight — 2026-09-26, correcting the one above.** *The broker is not a
+> compatibility module at all, and the sentence does not become true.* The insight above said
+> [ADR 0125](0125-the-bus-is-the-only-broker.md) would make "one purpose — the predecessor's
+> clients" true by moving the mesh's own modules off it.
+> [ADR 0127](0127-amqp-is-a-provision-not-the-bus.md) supersedes that: nothing moves off, because
+> a module may legitimately need an AMQP broker as a backing service the way it needs a database.
+> The broker becomes **an ordinary provider module** — no seat, not foundation, not raised at
+> genesis, and with no retirement condition, because the day its last client disappears is not a
+> day anything is waiting for. What this record decided — the mesh's bus is NATS — is untouched
+> by both; what was wrong was the sentence describing what happens to the old server, twice.
+
 ## References
 
 - [research 014](../01-RESEARCH/014-the-bus-on-nats/00-overview.md)

02-DECISIONS/0110-a-seat-is-a-module-assignment-from-a-closed-set.md

@@ -9,6 +9,17 @@ extends: 0009-modules-and-the-graph.md
 
 # 110. A seat is held by one assignment, from a closed set, and it may deliver a provision
 
+> **Narrowed, not replaced — 2026-09-27, on merging two lines of work.** This was marked superseded by
+> [ADR 0126](0126-a-module-declares-its-own-seats.md), and that overstated it: 0126 says in as many
+> words that *"everything 0110 decided about what a seat is stands untouched"*. What moved is where the
+> set lives and who may add to it —
+> [0126](0126-a-module-declares-its-own-seats.md) lets a module declare one and makes the set derived,
+> [0121](0121-a-system-seat-is-named-for-its-scope-and-modules-define-their-own.md) names the mesh's own
+> for their scope, and [0122](0122-a-seat-is-data-a-rename-is-a-database-update.md) moves them out of
+> code into a table. **What a seat *is* — one holder at its scope, a definition saying what a module
+> can hold against an assignment saying what it does, a role made singular rather than a module — is
+> this record and still current**, which is why those three rest on it.
+
 ## Context
 
 [ADR 0009](0009-modules-and-the-graph.md) introduced claims: a module declares something

02-DECISIONS/0112-a-module-definition-names-no-node-mesh-or-path.md

@@ -1,6 +1,6 @@
 ---
 topic: what runs on it
-status: proposed
+status: accepted
 date: 2026-09-25
 deciders: jochen
 reconstructed: false

02-DECISIONS/0118-undeclaring-gives-a-unit-back-the-state-it-was-found-in.md

@@ -40,7 +40,7 @@ undeclare can do. Found reviewing the uplink modules
 - the uplink modules would have stopped the network manager, taking the machine off the only
   link the mesh reaches it by.
 
-[ADR 0117](0117-a-machines-uplink-is-a-seat.md) answered that for its own modules with a
+[ADR 0125](0117-a-machines-uplink-is-a-seat.md) answered that for its own modules with a
 service declared with no `state`. Every other module that declares a unit it did not make is
 exposed in the same way, and relying on each author to remember an opt-out is how the next one
 is missed.
@@ -91,7 +91,7 @@ records the state it first found the unit in, and undeclaring returns the unit t
 - The service's settings the mesh wrote are given back by their own resources (a kept original
   restored, a region or keys removed). A running service keeps running on what it read until it
   next reads its configuration; the mesh does not restart it to make it notice.
-- A service declared with no `state` (ADR 0117) remains the way to say the mesh must not
+- A service declared with no `state` (ADR 0125) remains the way to say the mesh must not
   **start** a unit either; undeclared, it is forgotten.
 
 ## Consequences
@@ -113,7 +113,7 @@ records the state it first found the unit in, and undeclaring returns the unit t
 ## References
 
 - [issue 130](../04-ISSUES/130-undeclaring-a-service-stops-it/00-report.md): the finding
-- [ADR 0117](0117-a-machines-uplink-is-a-seat.md): the uplink modules, and a service with no state
+- [ADR 0125](0117-a-machines-uplink-is-a-seat.md): the uplink modules, and a service with no state
 - [ADR 0102](0102-the-mesh-writes-into-a-shared-file-never-over-it.md), [ADR 0100](0100-a-node-in-use-is-adopted-before-it-is-converged.md):
   what is given back, and how
 - mesh-host `internal/apply/apply.go` (`remove`, the service case)

02-DECISIONS/0119-a-taken-tunnels-predecessor-is-retired.md

@@ -53,7 +53,7 @@ is removed from where its unit reads it.**
   reporting it.
 - **The mesh never brings it back.** Undeclaring the private network does not restore the found
   tunnel: the mesh stopped it, and nothing is started on the way out
-  ([ADR 0118](0118-undeclaring-gives-a-unit-back-the-state-it-was-found-in.md)). A machine whose
+  ([ADR 0126](0118-undeclaring-gives-a-unit-back-the-state-it-was-found-in.md)). A machine whose
   private network is unassigned has no tunnel until it is assigned again — which is what
   unassigning it means.
 
@@ -83,5 +83,5 @@ is removed from where its unit reads it.**
 - [ADR 0105](0105-the-mesh-adopts-the-predecessors-tunnel-in-place.md): the take, and why it keeps
   the found configuration during it
 - [ADR 0100](0100-a-node-in-use-is-adopted-before-it-is-converged.md): kept originals
-- [ADR 0118](0118-undeclaring-gives-a-unit-back-the-state-it-was-found-in.md): nothing is started on the way out
+- [ADR 0126](0118-undeclaring-gives-a-unit-back-the-state-it-was-found-in.md): nothing is started on the way out
 - mesh-host `internal/apply/takeover.go`

02-DECISIONS/0120-a-roster-fact-carries-its-format-as-a-template.md

@@ -0,0 +1,136 @@
+---
+topic: what runs on it
+status: accepted
+date: 2026-09-27
+deciders: jochen
+reconstructed: false
+extends: 0112-a-module-definition-names-no-node-mesh-or-path.md
+---
+
+# 120. A roster fact carries its format as a template: the mesh owns the data, the module owns the format
+
+## Context
+
+A **fact** is a thing only the mesh knows — which machines exist, what they are called, where they
+are — written into a file where a module asks for it. The mesh computes it from the graph; a module
+loads it, restarts on it, does what its software does with it. Facts replaced three modules that
+existed only because computed output needed somewhere to live and ran no software of their own
+([ADR 0040](0040-what-a-module-is.md)).
+
+But the *format* lived in the control plane. A fact was a name from a closed list, and each name had
+a formatter written in Go beside the others: `node-names` wrote the roster as an `/etc/hosts` file,
+`node-zones` wrote it as a dnsmasq resolver's `local=`/`address=` lines. Adding a consumer meant
+adding a formatter — in the consumer's own configuration language — to the mesh.
+
+The ssh work made the cost plain. An operator's `~/.ssh` wants three roster projections — a
+`known_hosts`, an ssh `config` of `Host` blocks, an `authorized_keys` — each in ssh's syntax. Under
+the closed list that is three more formatters in the control plane, teaching it ssh's configuration
+language. And it does not stop at ssh: every daemon that reads the roster in its own file format
+would put its grammar here. The control plane was accreting the configuration languages of software
+it does not run — the exact thing [ADR 0040](0040-what-a-module-is.md) says is a
+module's and not the mesh's.
+
+The shape underneath is one shape. WireGuard's `[Peer]` blocks, `/etc/hosts`, dnsmasq's zones, an
+ssh `known_hosts` — all of them are *the roster, projected into a file*. Only the projection differs,
+and the projection belongs to whoever runs the software that reads it.
+
+## Considered Options
+
+**1. Keep the closed list; add a formatter per consumer.** Rejected. The control plane learns the
+configuration language of every daemon any module might run, without bound, and each format lives in
+the mesh rather than in the module that owns the file. A module cannot change how its own file is
+written without a control-plane change.
+
+**2. A general placeholder vocabulary over `content`, like `${machine:address}` but for the
+roster.** Rejected. The mesh's other substitutions each resolve to *one* scalar — this machine's
+address, one provider's port. The roster is inherently a *repetition*: one block per machine. A flat
+`${…}` vocabulary cannot iterate, and a mechanism that could would be a template in all but name.
+
+**3. The module gives a path and a template over the roster; the mesh renders it.** Chosen. The mesh
+owns the data — who exists, their names and addresses — and hands it to a Go `text/template` the
+module wrote. The mesh renders and reads neither the template's intent nor the file's meaning.
+
+## Decision
+
+**A fact is a path and a template.** In a module's manifest, `facts` maps a name the module chooses
+to a `{ path, template }`. The template is a Go `text/template` over a fixed **roster view**:
+
+- `.Node` — this machine's bare name.
+- `.Suffix` — what a mesh name ends in (`internal`, or the operator's choice), as composed.
+- `.Names` — every name the mesh serves: the machines *and* the names it was told to route.
+- `.Machines` — only the machines that are nodes of this mesh.
+
+Each of `.Names` and `.Machines` is a list of `{ Name, FQDN, Address }`. A machine the mesh has a
+record for but cannot yet place has no address and is left out of both — a name that resolves to
+nothing is a connection that hangs, so it is omitted rather than written (the same rule as before).
+
+**The mesh owns the data; the module owns the format.** The control plane holds **no** formatter.
+The two built-in projections render through the same path any module uses:
+
+- **`/etc/hosts`** is a template on the mesh's own network module. The mesh writes `/etc/hosts`
+  because being on the private network is what gives a machine a name — but the *layout* is a
+  template like any other, shipped with the control plane because that module ships with it, not
+  because the control plane knows the hosts-file format.
+- **dnsmasq's zones** move into dnsmasq. The `local=`/`address=` grammar is dnsmasq's configuration
+  language, and it now lives in dnsmasq's manifest, where the module that runs dnsmasq owns it.
+
+**A fact also says whether its file is the mesh's whole or a region of the machine's.** A hosts file
+is the machine's — its `localhost`, the operator's lines, another tool's marked blocks — so
+`node-names` is `shared`: the mesh owns only its region and keeps the rest byte for byte, the host
+laying it down `into: block`
+([ADR 0102](0102-the-mesh-writes-into-a-shared-file-never-over-it.md), hq issue 128). A resolver's
+zones file is the mesh's whole, and is not shared. The template renders the content either way;
+`shared` decides how the host writes it. This composes with hq 128 rather than replacing it: the
+region *mechanism* is the host's, the region's *format* is the module's template.
+
+**The names-vs-machines distinction is the template's choice** ([04-ISSUES/111](../04-ISSUES/111-the-resolver-is-told-names-the-mesh-serves-not-only-machines/00-report.md)):
+a container's hosts ranges `.Names`, so a routed name resolves to the machine serving it; a resolver
+told the mesh's suffix is its own ranges `.Machines`, or a routed name written there with the suffix
+appended is a name nobody will ever ask for.
+
+**A template that will not render is refused at composition, not on a machine.** A template that does
+not parse, or reads a field the roster does not have, fails where the manifest is — the closed-list
+safety, moved from the fact's *name* to the roster's *shape*. A daemon that starts, reads a file the
+mesh could not render, and answers nothing is a much worse way to find out.
+
+**WireGuard stays a computed generator, and that is the line.** Its `mesh0.conf` is not a pure roster
+projection — it carries topology the control plane decides: which peers are reachable, endpoints, hub
+forwarding, keepalive for a NAT'd node. And it is *foundational*: the overlay must be up before any
+module can be delivered, so the thing that writes it cannot itself be a delivered module. The line
+this draws: **the substrate that delivery rides on is the control plane's; everything layered on a
+working overlay is a roster template.** DNS, hosts, and ssh are layered; the overlay is the floor.
+
+## Consequences
+
+- **ssh is two templates and no control-plane change.** Once the roster view carries a machine's ssh
+  host key and its operator account ([to-be 29](../03-DESIGN/01-to-be/29-a-node-has-operator-accounts.md)),
+  `known_hosts`, the ssh `config`, and `authorized_keys` are templates on the ssh modules — the mesh
+  gains no knowledge of ssh's syntax. This ADR is what makes that work land without touching the
+  controller.
+- **A new roster projection never touches the control plane.** Any module that reads the roster in
+  its own format ships its own template.
+- **A module can change how its own file is written** without a control-plane change — it is editing
+  its own manifest.
+- **The schema changed and is not backward compatible.** A fact was a string (a path); it is now
+  `{ path, template }`. The old string form has no template and cannot be auto-upgraded, because the
+  format it implied was the formatter this ADR deletes. The controller and every catalogue module
+  using facts — only dnsmasq — land together. A controller and a catalogue that disagree cannot
+  compose the module: the running daemon on a machine is unaffected, but the mesh will not send it a
+  new declaration until both sides agree.
+- **The output did not change.** The `/etc/hosts` and dnsmasq zones a machine receives are
+  byte-for-byte what the deleted formatters wrote, pinned by tests that render the built-in template
+  and compose the real dnsmasq manifest.
+
+## References
+
+- [ADR 0040](0040-what-a-module-is.md): a module is software the mesh runs — a
+  format the mesh knows for software it does not run was the accretion this stops
+- [ADR 0112](0112-a-module-definition-names-no-node-mesh-or-path.md): a module definition names no
+  path; this is its sibling for content — a module definition names no format the mesh must know
+- [to-be 29](../03-DESIGN/01-to-be/29-a-node-has-operator-accounts.md): the ssh consumer this
+  unblocks, and the roster fields it will add
+- [04-ISSUES/111](../04-ISSUES/111-the-resolver-is-told-names-the-mesh-serves-not-only-machines/00-report.md): every served name is not a
+  machine — now the template's choice of `.Names` or `.Machines`
+- mesh-controller `internal/catalogue/roster.go` (the mechanism), `internal/overlay/generator.go`
+  (the built-in `/etc/hosts` template), `internal/catalogue/manifest.go` (`RosterFile`)
+- mesh-catalog `modules/dnsmasq/module.json` (the zones template, dnsmasq's own)

02-DECISIONS/0121-a-system-seat-is-named-for-its-scope-and-modules-define-their-own.md

@@ -0,0 +1,132 @@
+---
+topic: what runs on it
+status: accepted
+date: 2026-09-27
+deciders: jochen
+reconstructed: false
+extends: 0110-a-seat-is-a-module-assignment-from-a-closed-set.md
+---
+
+# 121. A system seat is named for its scope, and a module may define its own
+
+## Context
+
+[ADR 0110](0110-a-seat-is-a-module-assignment-from-a-closed-set.md) made seats a closed set the
+control plane defines: a well-formed name no longer becomes a seat by being claimed, so a person can
+read what a mesh can have and who fills each role. It left two things unsettled that the growing set
+now exposes:
+
+- **The names carry no rule.** `mesh-controller`, `mesh-store`, `mesh-broker` are named for the mesh;
+  beside them sit `the-artifact-store`, `the-build-machine`, `the-dns-port`, `the-showcase`,
+  `the-uplink` — a second naming style with no principle behind it. A reader cannot tell a seat's
+  scope from its name, and the mesh's own roles do not look like the mesh's.
+- **The set is the *only* place a seat may be defined.** A module claiming any name not in the
+  control plane's set is refused. That is right for *system* roles — one broker, one packet filter
+  per node — but it means a module can never define a role of its own: a demo module's
+  `the-showcase`, a future application's coordination role, must be smuggled into the control plane's
+  set or not exist. The control plane ends up holding roles that are not the mesh's to define.
+
+Reviewing the set against these also found seats whose *scope* or *membership* is wrong, not just
+their name — the review is the occasion to fix those too.
+
+## Decision
+
+**A system seat — one the control plane defines — is named for its scope:**
+
+- **`mesh-*`** for a mesh-scoped seat: one holder in the whole mesh, a role the mesh has once
+  (`mesh-controller`, `mesh-store`, `mesh-broker`, `mesh-git`, …). A `mesh-*` seat is always held by
+  a module **on a named node** — `mesh-git` is gitea *on novox*, not "gitea"; another node running
+  gitea does not hold `mesh-git` unless it is the holder. The seat is the mesh's single answer for
+  the role, and which node answers is part of what the seat records.
+- **`node-*`** for a node-scoped seat: one holder per node, a role each machine has at most once
+  (`node-packet-filter`, `node-intrusion-prevention`, `node-uplink`, …).
+
+The three already-`mesh-*` seats keep their names; the rest are renamed by this rule. The scope a
+name declares must match the seat's actual scope — a `mesh-*` seat at node scope, or the reverse, is
+a contradiction the reader is entitled to trust is impossible.
+
+**The control plane defines only system seats. A module may define its own.** A seat named `mesh-*`
+or `node-*` is the control plane's, and claiming one the control plane does not define is refused as
+before. Any *other* name is a **module-defined seat**: valid when the module declaring the claim also
+declares the seat (its name, scope, and — if any — the protocol its holder speaks). The control plane
+enforces one-holder-per-scope for it exactly as for its own, but does not otherwise know what it
+means. So an application can coordinate its own instances through a seat of its own, and the mesh's
+closed set stays what its name says it is: the *system's* roles, not everyone's.
+
+**Specific seats this settles:**
+
+- **`the-build-machine` → `mesh-build-machine`, and its scope becomes mesh.** There is one build
+  machine in the mesh (the builder on novox), not one per node. Node scope said the opposite. It
+  delivers no provision; it is the mesh's single build machine.
+- **`the-private-network` → `mesh-private-network`, held by the network *server* on one node.** Today
+  it is node-scoped and held on every node, with a stated (untested) story that a different VPN could
+  hold it per machine — which would force every provider module to independently implement receiving
+  and applying the controller-composed configuration. The mesh does not work that way and should not
+  pretend to: **one mesh decides one private network.** The seat is mesh-scoped, held by the server
+  module (WireGuard on the hub, novox). A machine that joins is given a **client module** that
+  receives the composed configuration and applies it; when a node joins, the mesh emits each node's
+  configuration so all of them know each other at once. This drops per-node VPN choice deliberately —
+  the private network is nox-mesh's own, and it defines the nodes' configuration rather than being
+  assembled from each node's opinion. (Implementation: the overlay generator's per-node computation
+  is unchanged; what changes is the seat's scope and the server/client split of the module.)
+- **`the-showcase` → removed from the set; it becomes a module-defined seat.** It is a demo module's
+  own coordination role, claimed by nothing else and held nowhere. It is the first module-defined
+  seat, and the reason the rule above is needed rather than hypothetical.
+- **`the-dns-port` → `node-dns-resolver`** (the daemon that binds `:53`), kept distinct from
+  **`the-resolver-configuration` → `node-resolver-config`** (what writes `resolv.conf`). Two roles,
+  two seats; the rename must not blur them.
+- **`the-packet-filter` → `node-packet-filter`** and **`the-intrusion-prevention` →
+  `node-intrusion-prevention`** — names kept as-is but for the prefix. "Packet filter" stays distinct
+  from "firewall", which would swallow intrusion-prevention too.
+- **`the-uplink` → `node-uplink`** ([ADR 0125](0117-a-machines-uplink-is-a-seat.md)). Unheld, so it
+  renames with no migration.
+- **The registry seats — `the-artifact-store`, `npm-package-registry` (→ `mesh-artifact-store`,
+  `mesh-npm-package-registry`) — and `git` (→ `mesh-git`) — are decided but deferred.** They each
+  *deliver* a provision, so renaming them is a delivering-seat migration: a holder that stops
+  resolving mid-flight takes a provision away from every consumer. That risk is not worth carrying in
+  the same pass as the node-* renames, so they keep their names until done deliberately.
+
+**`distribution` stays the mesh's registry; only `verdaccio` is retired.** An earlier draft of this
+record had the registry consolidating onto gitea and `distribution` retired — that was reversed:
+`distribution` is the standalone OCI registry serving every `artifact-store://…@sha256` image (the
+control plane's own included), and the mesh keeps it. `verdaccio` was a *second* npm registry;
+gitea already provides `npm-package-registry`, so verdaccio is redundant and is removed. It is only
+in the catalogue (never registered in the running mesh), so removing it is deleting the module — no
+migration, nothing to strand.
+
+## Consequences
+
+- **A reader learns a seat's scope from its name.** `mesh-*` is mesh-wide and one; `node-*` is
+  per-machine. The mesh's own roles finally look like the mesh's.
+- **Applications get their own seats** without the control plane learning their meaning. The closed
+  set shrinks to what it should be — the system's roles — and stops being where unrelated roles hide.
+- **The renames are a coordinated migration, not a rename.** A held seat's name lives in three places
+  that must move together: the control plane's set (`seats.go`), every claiming manifest, and what
+  each node reports it holds (re-derived by re-registering the manifest and re-pushing). A seat
+  renamed in one place and not the others stops resolving to its holder — and for a *delivering* seat
+  (`mesh-store`→postgres, `mesh-broker`→amqp, the registry seats) that is a mesh-wide provision
+  outage, the same failure mode as a schema change hitting an old manifest. So: the non-delivering
+  `node-*` seats and `mesh-build-machine` migrate as one tested controller+catalogue change;
+  `node-uplink` is free (unheld); the delivering registry seats are deferred to their own pass.
+- **The node-* migration was done as one controlled step, and it froze briefly.** Deploying the new
+  controller made it reject the still-old-named claims in the stored manifests, so composition stopped
+  for the affected nodes until each manifest was re-registered under its new name; running services
+  were untouched, and the window was seconds. This is the coordinated-migration cost named above,
+  paid once — and the reason the *delivering* registry seats, whose freeze would be a provision
+  outage rather than a compose pause, are not folded into the same pass.
+- **`distribution` is not retired.** It stays as the registry; only `verdaccio` (a redundant second
+  npm registry) is removed. The mesh keeps one OCI registry (`distribution`) and gitea for npm/git —
+  the "one registry, on gitea" idea was considered and dropped.
+- **The private network stops pretending to be swappable per node.** The gain is a coherent
+  server/client model matching how the controller already composes configuration; the cost is that
+  choosing a different VPN is now a mesh-wide change, not a per-node one — accepted.
+
+## References
+
+- [ADR 0110](0110-a-seat-is-a-module-assignment-from-a-closed-set.md) — the closed set this refines
+- [ADR 0125](0117-a-machines-uplink-is-a-seat.md) — `the-uplink`, renamed here to `node-uplink`
+- [ADR 0079](0079-the-foundation-seats-are-named-after-their-servers.md) — the original `mesh-*` seats
+  whose naming this generalises
+- [to-be 26](../03-DESIGN/01-to-be/26-the-seats.md) — the seat table, updated by this
+- mesh-controller `internal/catalogue/seats.go` (the set and claim validation),
+  `internal/overlay/generator.go` (the private network as server + client)

02-DECISIONS/0122-a-seat-is-data-a-rename-is-a-database-update.md

@@ -0,0 +1,107 @@
+---
+topic: what runs on it
+status: accepted
+date: 2026-09-27
+deciders: jochen
+reconstructed: false
+supersedes-in-part:
+  - 0110-a-seat-is-a-module-assignment-from-a-closed-set.md
+  - 0121-a-system-seat-is-named-for-its-scope-and-modules-define-their-own.md
+---
+
+# 122. A seat is data the controller owns, and a rename is a database update
+
+## Context
+
+[ADR 0110](0110-a-seat-is-a-module-assignment-from-a-closed-set.md) made the seats a closed set the
+control plane defines, and [ADR 0121](0121-a-system-seat-is-named-for-its-scope-and-modules-define-their-own.md)
+named them by scope. Both were right about *what* a seat is. Both left it defined the wrong *way*:
+**the set is a hardcoded Go slice compiled into the controller, and everything references a seat by
+its name as a string literal.** Renaming `the-packet-filter` to `node-packet-filter` this session
+took, in one pass:
+
+- an edit to the Go slice in `internal/catalogue/seats.go`, recompiled into a new controller image;
+- an edit to a `const gitSeat = "git"` in *production* control-plane code (`source.go`), because a
+  seat's name was hardcoded where a repository's home is resolved;
+- edits to every claiming manifest in the catalogue, each re-registered;
+- a controller **rebuild and redeploy**, which — because the running controller then refused the
+  still-old-named claims in stored manifests — **froze composition** for the affected nodes until
+  each manifest was re-registered under its new name;
+- the same coupling in the **build machine**, which embeds the same seat set and refused to build
+  anything claiming a name it did not yet know;
+- a **deadlock** when the build machine's own seat was renamed, since the old builder could not
+  build the new builder whose manifest claimed a name it rejected.
+
+None of that is what a rename should cost. A rename is the operator changing a label. It should be a
+single write, and nothing should have to be rebuilt, refused, or unfrozen. The set being *closed*
+(0110) and *named by scope* (0121) are good rules; **the set being code is the mistake.** When
+adhering to the design means twenty steps and a `const` in the resolver, the design is what to fix.
+
+## Decision
+
+**The seat set is data the control plane owns, not code it is compiled from.** The seats live in a
+table in the controller's store — one row per seat: a **stable id**, a `name`, a `scope`, what it
+`delivers` (a provision, or nothing), and the record that decided it. The rows are seeded by a
+migration (the closed set 0110 defines still ships with the mesh), and thereafter they are ordinary
+data the control plane reads and writes.
+
+**A seat is referenced by its stable id, never by its name.** A claim, a held-seat record, and any
+control-plane code that must name a seat (the git-seat resolver, the artifact-store guard) hold the
+**id**. The `name` is a label for people and for what a manifest writes; it is resolved to an id
+once, when a claim is registered. So:
+
+- **A rename is one `UPDATE seats set name = … where id = …`.** Nothing is recompiled, nothing is
+  re-registered, nothing is refused, nothing freezes. Held records and claims already point at the
+  id, so they follow the rename for free. The build machine is not involved, because the build
+  machine validates a claim against the set it reads from the mesh, not one baked into its image.
+- **Adding or removing a seat is an `INSERT`/`DELETE`** (within the closed-set discipline: a change
+  to the set is still a decision with a record — the record is now a row's `decided` column and an
+  ADR, not a line of Go). No controller release is needed to change the roster of roles.
+- **Production code stops hardcoding names.** `const gitSeat = "git"` becomes a lookup of the seat
+  that delivers the `git` provision (or a well-known id), so renaming its label cannot break the
+  code that finds a repository's forge.
+
+**What does not change** (0110 and 0121 still hold): a seat is still a module assignment from a
+closed set; there is still one holder per scope; a delivering seat is still the single answer for
+its provision; system seats are still `mesh-*`/`node-*` and a module may still define its own. Only
+their *storage and reference* change — from a compiled slice keyed by name to a table keyed by id.
+
+**A manifest still claims by name, and that is fine.** A manifest is written by a person and names
+the seat in words; the mesh resolves the name to an id at registration and stores the id. If a
+seat's name changes, manifests written against the old name are updated in the catalogue like any
+other edit (and the mesh can keep the old name as an alias row during a transition so nothing breaks
+in the window) — but the *control plane* never has to change or redeploy for it, which is the whole
+point. The heavy, mesh-wide, freeze-prone half of a rename disappears; only the ordinary catalogue
+edit remains.
+
+## Consequences
+
+- **A rename, and a set change, become operations, not releases.** The pain this session paid —
+  three freezes, a builder deadlock, hand-resolved manifests — is designed out. The seat migrations
+  still outstanding (the delivering registry seats, and the private network's scope change) should
+  wait for this: done as data, each is a write, not a coupled multi-repo deploy.
+- **The controller gains a small table and a seed migration**, and its seat lookups change from
+  slice scans to id-keyed reads. `SeatNamed`, `SeatDelivering`, `claimProblems` read the table.
+- **The build machine reads the set from the mesh** (it already talks to the control plane), rather
+  than embedding it — which removes the controller/builder seat coupling that made every breaking
+  seat change a two-sided deadlock (see [to-be 30](../03-DESIGN/01-to-be/30-the-mesh-updates-itself-on-a-push.md)).
+- **The closed set is still closed.** Data being editable is not the set being open: changing it is
+  still a decision, still recorded. What changes is that recording it no longer means shipping a
+  binary.
+- **This is a real refactor**, touching the store schema, the seat lookups, claim registration
+  (name→id resolution), and the held-seat records. It is worth its own build; until it lands, the
+  current compiled set stands and further renames are held rather than forced through the heavy path.
+- **Config on a seat is still the module's** (the question that surfaced this): a seat row carries
+  the seat's own metadata (scope, delivers, protocol), not a module's configuration — that stays in
+  the holding module's manifest ([ADR 0046](0046-a-module-configuration-is-its-assignments-not-its-manifest.md)). Making
+  seats data does not make them a config store.
+
+## References
+
+- [ADR 0110](0110-a-seat-is-a-module-assignment-from-a-closed-set.md),
+  [ADR 0121](0121-a-system-seat-is-named-for-its-scope-and-modules-define-their-own.md) — the seat
+  rules this keeps, whose *storage* it changes
+- [to-be 30](../03-DESIGN/01-to-be/30-the-mesh-updates-itself-on-a-push.md) — the controller/builder
+  seat coupling and the breaking-change freeze this removes for seat changes
+- mesh-controller `internal/catalogue/seats.go` (the compiled slice this replaces),
+  `cmd/mesh-controller/source.go` (`const gitSeat`, the hardcoded name this removes)

02-DECISIONS/0125-the-bus-is-the-only-broker.md

@@ -0,0 +1,133 @@
+---
+topic: the mesh
+status: superseded
+superseded-by: 02-DECISIONS/0127-amqp-is-a-provision-not-the-bus.md
+date: 2026-09-26
+deciders: jochen
+reconstructed: false
+extends: 02-DECISIONS/0106-the-bus-is-nats.md
+---
+
+# 125. The bus is the only broker
+
+## Context
+
+[ADR 0106](0106-the-bus-is-nats.md) moved the mesh's bus to NATS and kept the AMQP broker "as a
+module with one purpose — the predecessor's clients", retiring with the last of them.
+[Design 25](../03-DESIGN/01-to-be/25-the-bus-on-nats.md) repeats that: a compatibility module with
+a single purpose and a retirement condition.
+
+**It is not single-purpose, and was not when that was written.** Two modules of the *new* mesh
+declare `requires: ["amqp"]` and are answered by the broker module's own provisioner:
+
+- `amqp-ping`, whose source says it "exists to PROVE the grant end to end: the mesh gave it a
+  scoped login and a vhost of that name on the lavinmq provider";
+- `amqp-email-forwarder`, which uses it for work.
+
+What that provisioner answers is **not the mesh's bus**. Its own comment draws the line: a
+consumer gets "its own message broker, isolated from every other consumer's by the vhost
+boundary… a broker of its own, not a shared account on the mesh's control-plane broker" —
+vhost-per-login, "the exact analog of postgres's database-per-login."
+
+So two different things wear the word *broker*: the mesh's nervous system, and a private message
+broker handed to a module as a resource, the way a database is. The first is being replaced. The
+second was never examined, and on the retirement condition ADR 0106 sets, it disappears with no
+successor and nothing notices — a module of the new mesh left requiring something no provider
+answers.
+
+The operator's direction, asked at the point this surfaced: **NATS is the heart of the
+application** — not a component it contains, and not a thing to reproduce the predecessor's
+shapes on.
+
+## Considered Options
+
+1. **Carry the private broker forward onto NATS** — each requiring module gets its own NATS
+   account, provisioned like a database. Rejected on three counts. It reproduces the
+   predecessor's shape on the new bus, which is the thing this whole move exists to stop. It
+   gives the mesh two messaging models, so "how does a module send a message" has two answers
+   depending on a manifest line. And NATS accounts isolate subject spaces *entirely*: a module
+   inside its own account cannot reach the mesh's bus at all, so it would hold two connections
+   and two identities to do one job.
+2. **Keep the compatibility broker indefinitely** for the mesh's own modules. Rejected: its
+   retirement condition is the point of it. A module of the new mesh depending on the retired one
+   keeps the predecessor alive permanently, which is the opposite of a compatibility module.
+3. **One bus. A module's messaging is subjects on it, scoped by what it declares.** Adopted.
+
+## Decision
+
+**The bus is the only broker.** NATS is the mesh's one messaging system, and every module's
+messaging is subjects on that bus under its own account, scoped by its `emits` and `consumes`
+([ADR 0043](0043-a-module-broker-account-is-scoped-by-emits-and-consumes.md)). There is no second
+broker, and none is handed to a module as a resource.
+
+**The `amqp` interface is not carried forward.** It leaves the set of things a module may require
+and retires with the compatibility broker rather than gaining a successor.
+
+Concretely, in the controller's seat table: **the `mesh-broker` seat delivers nothing.** It
+currently reads `Delivers: "amqp"` — the seat's holder answers a requirement for a broker — and
+under this decision it joins `mesh-controller` and `the-catalogue`, the foundation seats that
+deliver no provision at all. The bus is not something a module asks for; it is what a module is
+reached through.
+
+- `amqp-email-forwarder` moves to the bus like any module: what it emits and consumes, declared,
+  and the account follows.
+- `amqp-ping`'s *purpose* is kept and its mechanism is not. Proving end to end that a module
+  receives scoped messaging it did not configure itself is worth a probe; it becomes a probe of
+  the bus, and its assertion changes from "I reached my own vhost" to "I reached exactly my
+  subjects and was refused the rest."
+
+**A module that wants a queue of its own has one already**: a subject nothing else may publish to
+and a durable consumer of its own, both derived from its declaration. What it does not get is a
+server of its own.
+
+**The mesh's own streams are the controller's, created at genesis, not provisioned** — and
+`EVENTS` is one stream, closing the question [design 25](../03-DESIGN/01-to-be/25-the-bus-on-nats.md)
+§11 left open. The reason is not preference but **bootstrapping**: a provisioner is a module, and
+a module needs a bus account before it can run at all. Anything the bus itself is made of must
+exist before the first module starts, so it is composed as configuration
+([ADR 0106](0106-the-bus-is-nats.md): never through a management API) rather than provisioned by
+something that could not yet be running.
+
+## Consequences
+
+- **Design 25 gains the distinction and loses the "single purpose" claim**; its §11 question about
+  the `EVENTS` stream closes here.
+- **Nothing in [design 27](../03-DESIGN/01-to-be/27-a-module-requires-the-mesh-resolves.md)'s
+  model changes** — the four provider kinds, the contract, resolution all stand, and it never
+  enumerated interfaces, so there is nothing to strike from it. What changes is that messaging
+  leaves the set of things resolved at all: every module has it by existing.
+- **One line of the controller's seat table changes**, and it is the load-bearing one:
+  `mesh-broker` stops declaring what it delivers. A requirement for `amqp` then resolves to
+  nothing and is refused at assignment, which is how the two modules below are found rather than
+  discovered at runtime.
+- **Two modules have conversion work**, and it belongs to step 4 of
+  [ADR 0116](0116-the-bus-is-built-in-five-steps.md), with the flows. Neither blocks step 1.
+- **The compatibility broker becomes what ADR 0106 already called it** — single-purpose — once
+  those two have moved. That record's claim was wrong when written and is made true by this one.
+- **What got harder:** a module that genuinely wanted an isolated server — a tenant boundary at
+  the broker rather than at the subject — no longer has that option, and would have to argue for
+  it as a new decision. That is the intended cost: one bus is the point.
+
+## How it is checked
+
+- **A module's messaging works with no `requires` line for it.** A lab bed: a module declaring
+  only `emits` and `consumes` reaches its subjects, and is refused every other — which is
+  [ADR 0116](0116-the-bus-is-built-in-five-steps.md) step 1's permission bed, already required.
+- **Nothing requires `amqp`.** With the seat delivering nothing, a module still declaring it is
+  refused at resolution — the existing "requirement no provider answers" path, not a new check. A
+  catalogue test asserts no module declares it once the two have moved.
+- **The probe proves the claim it is named for.** `amqp-ping`'s successor fails if a module can
+  reach a subject outside its declaration, not merely if it cannot reach its own.
+- **The compatibility broker's retirement condition can actually be met.** A check that no module
+  of the mesh — as opposed to a predecessor client — holds a connection to it.
+
+## References
+
+- [ADR 0106](0106-the-bus-is-nats.md) — the bus is NATS; corrected here on what the compatibility
+  broker serves.
+- [ADR 0116](0116-the-bus-is-built-in-five-steps.md) — the steps; the conversions land in step 4.
+- [ADR 0043](0043-a-module-broker-account-is-scoped-by-emits-and-consumes.md) — the scoping that
+  makes one bus safe.
+- [design 25](../03-DESIGN/01-to-be/25-the-bus-on-nats.md),
+  [design 27](../03-DESIGN/01-to-be/27-a-module-requires-the-mesh-resolves.md) — the two documents
+  this changes.

02-DECISIONS/0126-a-module-declares-its-own-seats.md

@@ -0,0 +1,145 @@
+---
+topic: the tiers
+status: accepted
+date: 2026-09-26
+deciders: jochen
+reconstructed: false
+extends: 02-DECISIONS/0110-a-seat-is-a-module-assignment-from-a-closed-set.md
+---
+
+# 126. A module declares its own seats; the mesh reserves its own
+
+## Context
+
+[ADR 0110](0110-a-seat-is-a-module-assignment-from-a-closed-set.md) closed the set of seats. Its
+evidence was strong and still is: nothing could answer *which seats does this mesh have, and who
+holds each*. Answering it meant reading every manifest in two repositories and then the
+controller's own code, and when that enumeration was done by hand while writing the record, **it
+reported eleven claims where there were thirteen.** The fix was a table in the controller, and
+adding a seat became a decision.
+
+What that table cannot express is the architecture [ADR 0125](0125-the-bus-is-the-only-broker.md)
+opened. With one bus and no private brokers, a module offering a service to other modules offers
+it as **a role on the bus**: a set of subjects, exactly one holder, addressed by what it does
+rather than by which module or node provides it. A telegram sender, a licensing master, anything
+a mesh might want one of. Under a closed table, adding any of those means editing the controller
+— so a capability contributed by a module would require a change to the mesh itself, which is the
+coupling the module system exists to prevent.
+
+**The two requirements look opposed and are not.** 0110 needs the set *enumerable*. The
+architecture needs it *extensible*. Those conflict only if enumerable means *written down in one
+place by hand* — which is exactly the property that let the count drift in the first place.
+
+## Considered Options
+
+1. **Keep the closed table, add each new seat by decision.** Rejected. Every capability a module
+   contributes would need a change to the controller and a record before it could be offered, and
+   the mesh would carry the names of services it does not itself implement.
+2. **Free-form seats, as before 0110.** Rejected for 0110's own reason, unchanged: nothing can
+   say what a mesh has, and a name invented at a claim site is a name nobody can explain later.
+3. **A set that is closed at any moment and derived rather than maintained**, with the mesh's own
+   seats reserved by name. Adopted. 0110 weighed options 1 and 2 and never considered this one.
+
+## Decision
+
+**A seat may be declared by a module, and the set of seats a mesh has is derived: the mesh's own,
+plus those declared by every module it has registered.** The set is still closed — a seat named
+nowhere is refused — but it is computed from the catalogue rather than written in the controller.
+
+Everything 0110 decided about what a seat *is* stands untouched: one holder at its scope; a
+definition says which seats a module *can* hold and an assignment says which it *does*; holding
+one may deliver a provision; a seat makes a role singular, never a module.
+
+**Enumeration is a query, not an inventory.** The catalogue knows every registered manifest, so
+"which seats does this mesh have, and who holds each" is answered by asking it. This is a
+stronger answer than the table gave, not a weaker one: a derived list cannot drift from reality,
+and drift is how the hand-made count came out at eleven of thirteen.
+
+**The mesh's own seats are reserved by prefix.** Every seat the mesh itself defines is named
+`mesh-*`, and a module declaring any `mesh-*` name is refused at registration. The prefix *is*
+the reservation rule — no list of reserved names to maintain, and no way for the mesh's own
+namespace to be colonised by a manifest. This requires renaming the seats that drifted from
+[ADR 0079](0079-the-foundation-seats-are-named-after-their-servers.md)'s convention: `the-catalogue`
+becomes `mesh-catalog`, `git` becomes `mesh-git`, and the node-scoped `the-build-machine`,
+`the-dns-port`, `the-intrusion-prevention`, `the-packet-filter`, `the-private-network`,
+`the-resolver-configuration`, `the-showcase` take the same prefix.
+
+The mesh's seats stay the mesh's for a reason that does not apply to a module's: **the mesh's own
+code looks them up by name.** The resolver *is* the thing that finds the store. `mesh-store` is
+not a convention the controller follows, it is an identifier the controller dereferences.
+
+**A declared seat carries a protocol.** A module declaring a seat says what may be sent to it,
+what it emits, and what it serves. The holder must satisfy it; a module may not claim a seat whose
+protocol it does not implement. Callers declare that they use the *seat*, never the module, so
+replacing the implementation changes nothing for any caller.
+
+**A seat is for a role; an event stays addressed to its emitter.** The two are not
+interchangeable and the choice is not stylistic. An event is *this happened to me* — the emitter's
+identity is the meaning, which is why the envelope carries source, node and time
+([ADR 0042](0042-the-shape-of-an-event-on-the-wire.md)); routing it through a role would erase the
+provenance an audit needs. A seat is *this capability, whoever provides it* — where not knowing
+the holder is the point. Publish an event when the fact is about you; declare a seat when you are
+offering something another module could offer instead.
+
+**Two modules declaring the same seat name is refused at registration**, second one loses.
+Registration is the last moment the mesh can still say no, and a seat name meaning two different
+protocols is the failure nobody could diagnose afterwards.
+
+## Consequences
+
+- **The controller's seat table stops being the set** and becomes the mesh's own reserved entries.
+  Resolution reads the catalogue for the rest.
+- **Ten seats are renamed.** A rename is a migration, not an edit: existing assignments hold the
+  old names, so the change carries a mapping and is applied once, and the lab beds that name seats
+  are updated with it.
+- **A `uses` naming an undeclared seat is refused at registration**, which is where 0110's
+  guarantee lands under this model — the same refusal, at the same moment, from a derived set.
+- **Adding a capability stops requiring a decision record.** That is a real loss of governance and
+  the intended trade: the argument for a seat's existence moves into the module that declares it,
+  where it is reviewed as part of the manifest. The mesh's own seats keep the old bar.
+- **[ADR 0041](0041-events-are-a-relationship.md)'s machinery claim is already stale** for a
+  different reason, and is corrected in place there under the rule in
+  [`README.md`](README.md) — a progressive insight: on JetStream a subscription is a durable
+  consumer, a real object someone must create.
+- **What got harder:** a seat's protocol is now a compatibility surface between modules that do
+  not know each other. Changing one breaks callers already bound to it, and nothing here says how
+  that is versioned. It is the first thing to answer in the design, and the thing most likely to
+  hurt later rather than now.
+
+## How it is checked
+
+- **The overview answers, and is right.** A command lists every seat, its scope, its protocol and
+  its holder, derived from the catalogue — and a test asserts the count against a fixture mesh,
+  because an enumeration nobody checks is how thirteen became eleven.
+- **`mesh-*` is refused to a module.** A registration test: a manifest declaring `mesh-anything`
+  is refused, naming the prefix as the reason.
+- **An undeclared seat is refused.** A registration test on `uses`, and a resolution test that
+  nothing reaches runtime unresolved.
+- **A second declarer loses.** A registration test: two manifests, same seat name, the second
+  refused and the first untouched.
+- **A holder must satisfy the protocol.** A claim whose module does not serve what the seat
+  declares is refused at assignment, not discovered when a caller times out.
+
+## Progressive insight
+
+> **Progressive insight — 2026-09-26.** *A seat rename is not a data migration.* This record's
+> consequences say "a rename is a migration, not an edit: existing assignments hold the old
+> names, so the change carries a mapping and is applied once". Implementing it showed there is
+> nothing stored to migrate: a seat's holding is **derived at resolution** from the claims in
+> manifests (`resolve.go` builds it each time), never written down, so no recorded name is left
+> pointing at the old one. What exists is source — the controller's seat table, the manifests
+> that claim them, and a manifest that may be registered later from its own repository. So the
+> change is an edit plus a **kept** rename table, which tells a manifest written against an old
+> name what it became rather than refusing it as unknown.
+>
+> The decision — that modules declare seats, that the mesh reserves `mesh-*`, and that the ten
+> are renamed — is unchanged. Only the shape of the work was wrong.
+
+## References
+
+- [ADR 0110](0110-a-seat-is-a-module-assignment-from-a-closed-set.md) — superseded here; its
+  requirement is kept and only its mechanism replaced.
+- [ADR 0125](0125-the-bus-is-the-only-broker.md) — one bus, which is what makes a role addressable.
+- [ADR 0079](0079-the-foundation-seats-are-named-after-their-servers.md) — the naming convention
+  the reserved prefix restores.
+- [ADR 0041](0041-events-are-a-relationship.md) — the event half of the boundary drawn here.

02-DECISIONS/0127-amqp-is-a-provision-not-the-bus.md

@@ -0,0 +1,104 @@
+---
+topic: the mesh
+status: superseded
+superseded-by: 0131-everything-on-the-mesh-speaks-to-the-broker-seat.md
+date: 2026-09-26
+deciders: jochen
+reconstructed: false
+supersedes: 02-DECISIONS/0125-the-bus-is-the-only-broker.md
+---
+
+# 127. AMQP is a provision, not the bus
+
+## Context
+
+[ADR 0125](0125-the-bus-is-the-only-broker.md) decided that the bus is the only broker, and went
+one step further than it had grounds for: it also decided that the `amqp` **interface** — a module
+requiring a message broker of its own — "is not carried forward" and "retires with the
+compatibility broker rather than gaining a successor", with the two modules declaring it converted
+to the bus in step 4.
+
+The operator's correction: **AMQP is deprecated as the mesh's transport, not abolished as a
+service.** The broker module keeps running and keeps answering `amqp` requirements. It is no
+longer a core part of the mesh — *"it's just a module like mssql now."*
+
+**What 0117 conflated** is two different reasons a module might ask for a broker, which look
+identical in a manifest:
+
+1. **To talk to other modules.** Wrong under one bus, and the thing 0117 was right to refuse: a
+   private broker used as inter-module transport is a second bus, with every guarantee crossing a
+   seam and no scoping the mesh can see.
+2. **Because it genuinely needs an AMQP broker**, the way something needs a database — a queue for
+   its own internals, or interop with software that speaks AMQP and nothing else. That is a
+   backing service, and the mesh has a word for backing services already.
+
+0117 saw the first and legislated against both. The second is ordinary, and forbidding it would
+make the mesh unable to run a large class of perfectly normal software while claiming that as
+architecture.
+
+## Considered Options
+
+1. **Keep 0117 as written** — retire the interface, convert the two modules. Rejected by the
+   operator, and wrongly reasoned besides: it treats "needs an AMQP broker" as always a mistake.
+2. **Keep the broker as the predecessor's compatibility module**, as ADR 0106 framed it, with a
+   retirement condition. Rejected: it is not single-purpose and its clients are not only the
+   predecessor's, so the retirement condition describes a day that will not come.
+3. **The broker is an ordinary provider module of an ordinary provision.** Adopted.
+
+## Decision
+
+**The mesh's bus is NATS and only NATS.** Everything 0117 decided about *the bus* stands: one bus,
+a module's messaging is subjects on it scoped by what it declares, no module is handed a bus of
+its own, and the `mesh-broker` seat is the NATS server's.
+
+**`amqp` remains a provision a module may require**, answered by the broker module the way
+`postgres-database` is answered by the store module or a database is answered by mssql. It is not
+deprecated as an interface; the software behind it is simply no longer the mesh's nervous system.
+
+**The broker module stops being foundation.** It claims no seat — `mesh-broker` is the NATS
+server's — it is not raised at genesis, nothing in the mesh requires it, and a mesh that never
+installs it is a complete mesh. It is installed when something wants it, like any other provider.
+
+**The rule that survives, stated so it can be applied:** *inter-module communication goes over the
+bus.* A module may hold a broker, a database or a cache as a backing service; it may not use one
+as a channel to another module. The line is not which software is involved, it is whether a second
+module is on the other end.
+
+**Neither `amqp-ping` nor `amqp-email-forwarder` needs converting.** 0117 put that work in step 4;
+it is removed. They require a backing service and a provider answers.
+
+## Consequences
+
+- **The "compatibility broker" framing is wrong and goes.** There is no `lavinmq-compat`, no
+  single purpose and no retirement condition. Design 25 §5 is corrected.
+- **[ADR 0106](0106-the-bus-is-nats.md)'s progressive insight was itself wrong** and is corrected
+  by a second one there. It said 0117 would make 0106's "one purpose — the predecessor's clients"
+  sentence true by moving the mesh's modules off. Nothing moves off; the sentence is simply not
+  what the broker is.
+- **The seat change stands**, for a better reason than 0117 gave: not because a broker cannot be
+  provisioned, but because *this* broker is not the mesh's bus. The broker module drops its
+  `mesh-broker` claim and the `nats` module takes it.
+- **Step 4 loses two conversions**; step 1 and the WBS are otherwise unaffected.
+- **What got harder:** the rule is now a judgement rather than a prohibition. "Is this a backing
+  service or a channel to another module?" has to be asked in review, where 0117 could have
+  answered it with a parser. That is the honest cost of allowing the legitimate case.
+
+## How it is checked
+
+- **A module's own messaging needs no `requires`.** The check from 0117, unchanged: a module
+  declaring only `emits` and `consumes` reaches its subjects and is refused every other.
+- **The broker holds no seat.** A manifest test: the broker module claims nothing, and a mesh
+  raised without it is complete — genesis names it nowhere.
+- **`amqp` resolves like any provision.** A resolution test: a module requiring it is answered by
+  the provider, refused when none is assigned, and neither case touches the bus.
+- **What cannot be checked mechanically**, and is said rather than implied: that a module holding
+  a broker is not using it to reach another module. Review, not a parser.
+
+## References
+
+- [ADR 0125](0125-the-bus-is-the-only-broker.md) — superseded; its ruling on the bus is kept
+  whole and only its ruling on the interface is reversed.
+- [ADR 0106](0106-the-bus-is-nats.md) — the bus is NATS; its compatibility-broker framing is
+  corrected here.
+- [ADR 0126](0126-a-module-declares-its-own-seats.md) — seats, including the one the NATS server
+  now holds alone.

02-DECISIONS/0128-the-mesh-bus-is-required-not-ambient.md

@@ -0,0 +1,123 @@
+---
+topic: the mesh
+status: accepted
+date: 2026-09-26
+deciders: jochen
+reconstructed: false
+extends: 02-DECISIONS/0131-everything-on-the-mesh-speaks-to-the-broker-seat.md
+---
+
+# 128. The mesh bus is required, not ambient
+
+
+> **Pointer repointed, 2026-09-27.** This record was written extending
+> [ADR 0127](0127-amqp-is-a-provision-not-the-bus.md) (superseded by [ADR 0131](0131-everything-on-the-mesh-speaks-to-the-broker-seat.md)), which
+> [ADR 0131](0131-everything-on-the-mesh-speaks-to-the-broker-seat.md) has since superseded — AMQP is
+> not a provision at all. Nothing decided here changes; the frontmatter now rests on the live record,
+> and the citations below are read with that in mind.
+
+## Context
+
+[Design 29](../03-DESIGN/01-to-be/32-what-a-module-declares.md) opened by saying the bus is
+*ambient*: "No module requires it, the way no module requires a filesystem. Every module gets a
+connection and an identity whether it asks or not."
+
+**Two counts say that is wrong.** Of the 72 modules in the catalogue, **49 declare an own-secret
+named `broker` and 23 do not.** So the bus is not universal — nearly a third of the catalogue
+never speaks to it — and an ambient connection would mint an account, a password and a permission
+set for every one of those 23, each a credential nothing uses and everything must rotate.
+
+And the 49 that do take one **each hand-write the path it lands at**
+(`own-secrets: { broker: "/var/lib/<module>/broker" }`). That is a special case doing badly what
+provisioning already does well: a consumer names where a credential lands, the mesh seals it
+there, and rotation and removal follow the same path as every other credential.
+
+**The argument that made the bus ambient was narrower than it looked.**
+[ADR 0125](0125-the-bus-is-the-only-broker.md) reasoned that bus accounts cannot be provisioned
+because a provisioner is itself a module that needs an account before it can run. That is true of
+a **provisioner process**, and it is not true of a provision: the mesh's bus accounts are composed
+by the *controller*, into configuration, and the controller is not waiting on a bus account to
+exist. The circularity is real for one mechanism and absent for the other, and the earlier record
+applied it to both.
+
+## Considered Options
+
+1. **Keep the bus ambient.** Rejected on the counts above: it over-grants to 23 modules and keeps
+   a hand-written path in 49.
+2. **Derive the requirement** from whether a module declares any `emits`, `consumes`, `serves` or
+   `uses`. Rejected: it is the ambient model with extra inference. A reader of a manifest still
+   cannot see that the module holds a bus credential, and the rule would have to be re-derived
+   every time the set of bus-facing declarations grew.
+3. **The mesh bus is a provision a module requires**, delivered by the seat that holds it.
+   Adopted.
+
+## Decision
+
+**A module that speaks to the mesh requires `mesh-bus`, and receives what it needs to connect.**
+The contract is an address, a credential sealed to the module, and the trust to verify the
+server. It lands where the module's manifest says, like any provision. A module that does not
+require it gets no account, no password and no permissions — and 23 modules in the catalogue
+should get none.
+
+**The `mesh-broker` seat delivers `mesh-bus`.** Its holder is the mesh's own bus, and what
+holding it delivers is the connection to that bus — which is what a seat delivering a provision
+has always meant ([design 26](../03-DESIGN/01-to-be/26-the-seats.md)).
+
+**The requirement delivers the connection; the declarations shape the authority.** They are two
+different things and both stay explicit. `requires: mesh-bus` says *this module talks to the
+mesh*; `emits`, `consumes`, `serves`, `uses` and a declared seat say *what it may say and hear*,
+and the permission set is derived from those and nothing else
+([ADR 0043](0043-a-module-broker-account-is-scoped-by-emits-and-consumes.md)). Requiring the bus
+grants no subject; declaring a subject without requiring the bus is refused at registration as
+incoherent.
+
+**The `mesh-bus` provision is answered by the controller, not by a provisioner.** This is the
+surviving kernel of ADR 0125's bootstrap argument, narrowed to what it actually supports: the
+bus's accounts are configuration the controller composes and the server reloads
+([ADR 0106](0106-the-bus-is-nats.md) — never through a management API), so there is no provisioner
+process in the path and nothing waiting on a bus account to create bus accounts. It is a provision
+whose provider is the mesh itself.
+
+**A module may also provide a NATS server of its own, and that is a different interface.** Exactly
+as the AMQP broker provides `amqp` ([ADR 0127](0127-amqp-is-a-provision-not-the-bus.md) (superseded by [ADR 0131](0131-everything-on-the-mesh-speaks-to-the-broker-seat.md))), a module
+may run its own NATS and offer it as a backing service. That interface is **`nats`**; the mesh's
+own bus is **`mesh-bus`**; the two are never the same name, because a manifest that said `nats`
+could mean either and the difference is the whole architecture. The rule from 0119 decides which
+is legitimate: a private bus is a backing service, never a channel to another module.
+
+## Consequences
+
+- **Design 29's opening is reversed.** The bus is not ambient; it is required, and the document's
+  first paragraph says the opposite of this.
+- **The seat's `Delivers` is `mesh-bus`** — corrected twice in one day, which is worth recording
+  rather than tidying: it read `amqp`, which was the old broker's interface; ADR 0125 emptied it,
+  on the reasoning that a bus cannot be provisioned; and it is neither. The seat delivers the
+  mesh's bus.
+- **`own-secrets: { broker: ... }` is retired** in favour of the provision's own delivery, across
+  49 manifests. That is a mechanical change, and it belongs with the conversions in step 4 rather
+  than step 1.
+- **23 modules lose a credential they never used.** Not a regression — an over-grant removed, and
+  the smallest honest statement of what this buys.
+- **What got harder:** one more line in most manifests. The trade is that the line is true, and
+  its absence is also true.
+
+## How it is checked
+
+- **A module with no `requires: mesh-bus` has no account.** A composition test: the derived user
+  list contains exactly the modules that require it, and the 23 that do not appear nowhere in it.
+- **Declaring a subject without requiring the bus is refused.** A registration test on a manifest
+  with `emits` and no requirement, naming the contradiction.
+- **Requiring the bus grants no subject on its own.** A composition test: a module that requires
+  `mesh-bus` and declares nothing else gets a connection and an empty permission set.
+- **`nats` and `mesh-bus` are distinct interfaces.** A resolution test: a module requiring `nats`
+  is answered by a module providing it, never by the seat holder, and vice versa.
+
+## References
+
+- [ADR 0125](0125-the-bus-is-the-only-broker.md) — superseded by 0119; its bootstrap argument is
+  narrowed here to the case it supports.
+- [ADR 0127](0127-amqp-is-a-provision-not-the-bus.md) (superseded by [ADR 0131](0131-everything-on-the-mesh-speaks-to-the-broker-seat.md)) — a broker as a backing service; this
+  applies the same shape to the mesh's own bus and separates the two names.
+- [ADR 0043](0043-a-module-broker-account-is-scoped-by-emits-and-consumes.md) — authority from
+  declarations, which this leaves untouched.
+- [design 26](../03-DESIGN/01-to-be/26-the-seats.md) — a seat delivering a provision.

02-DECISIONS/0129-a-seat-carries-the-protocol-of-its-role.md

@@ -0,0 +1,102 @@
+---
+topic: the mesh
+status: accepted
+date: 2026-09-27
+deciders: jochen
+reconstructed: false
+extends: 02-DECISIONS/0122-a-seat-is-data-a-rename-is-a-database-update.md
+---
+
+# 129. A seat carries the protocol of its role
+
+## Context
+
+[ADR 0126](0126-a-module-declares-its-own-seats.md) let a module declare a seat with its protocol:
+what work the role accepts, what it emits, what it serves. A module's own seats work that way today.
+**The mesh's own seats — the `mesh-*` set — carry no protocol at all**, only a name, a scope and the
+provision they deliver. They say who does a job and nothing about what may be said to them or by
+them.
+
+That gap surfaced three times in one day, each time as a different-looking problem.
+
+**A build machine.** On the bus the mesh runs on today a builder has its own account kind, created by
+its own command, with permissions written by hand: read the build queue, write to two exchanges. One
+publish to a shared exchange reached all three audiences a finished build has — whoever asked, the
+controller that records it, and the catalogue that places it in the module graph. On a bus where
+permissions are per subject those are three separate grants, and nothing derives them, because a
+builder is not a module and holds a seat that promises nothing.
+
+**An event about a role rather than about a module.** The module holding the artifact-store seat
+declared an event named after a *different* module
+([issue 127](../04-ISSUES/127-a-module-event-derives-a-subject-nothing-publishes/00-report.md)). The
+bus refuses that, because a namespace belongs to who it is named for. The event is genuinely about the
+role — "the artifact store accepted an image" — and a consumer written against whichever module holds
+that role today breaks when the holder changes. There was nowhere else to put it.
+
+**A catalogue catching up.** The controller answers a request for builds it may have missed by
+re-publishing them under its own name, which no consumer of the builder's subject hears. Publishing
+them under the builder's name would be the controller signing an event as another module. Answering
+into the asker's inbox needs a grant over every inbox in the mesh, which
+[design 25](../03-DESIGN/01-to-be/25-the-bus-on-nats.md) §4 refuses.
+
+Three symptoms, one cause: **the mesh has roles it cannot describe.**
+
+## Decision
+
+**A seat carries the protocol of its role, whether the seat is a module's or the mesh's own.** The
+`mesh-*` set gains the same three fields a declared seat has — what it accepts, what it emits, what it
+serves — and the holder's authority, its work queue and its consumers are derived from them by the
+machinery that already does this for a module's seats.
+
+**Builds become work submitted to a role.** The build machine seat accepts a build and emits an
+outcome. The dedicated `mesh.build.*` branch and the stream behind it retire: a work queue shared by
+several build machines is exactly what a seat's `accepts` already is, and keeping a second mechanism
+for it means two things to reason about and two places for a permission to be wrong.
+
+**One publish still reaches three audiences, and now the mesh derived the subject.** A build's outcome
+is the seat's own event. Whoever asked matches it by the id their request carried; the controller
+records it; the catalogue places it. That is the fan-out the shared exchange gave for free, expressed
+as a subject rather than as a topology, and it means no holder needs permission to publish into
+anybody's inbox.
+
+## Alternatives considered
+
+**A dedicated principal kind for a builder**, mirroring the account the old bus issues it. Smaller: one
+addition to the composer, no change to seats, and it matches how a builder is treated today. Not taken
+because it answers one of the three symptoms and leaves the other two, and because "the builder is
+special" is a claim nobody could justify from the design — a build machine is a role the mesh has, and
+the mesh has a word for a role.
+
+**Leaving the outcome as a reply to the asker's inbox.** Rejected on authority: a holder able to answer
+any asker needs a grant across the whole inbox space, which is the one grant design 25 §4 refuses by
+name. The seat's event costs the asker a filter and costs the mesh nothing.
+
+## Reconciled with 0122, which landed in parallel
+
+*Added 2026-09-27, on merging.* [ADR 0122](0122-a-seat-is-data-a-rename-is-a-database-update.md) moved
+the seat set out of compiled code and into a table the controller owns. This record was written against
+the slice, and says the `mesh-*` set "gains the same three fields a declared seat has".
+
+**The decision is unaffected and the mechanism is better for it.** What a seat accepts, emits and serves
+becomes three columns beside its name and scope, so giving a role a protocol is a write rather than a
+rebuild — which is the whole argument of 0122 applied to the thing this record adds. Where this text
+says the set gains fields, read: the table gains columns.
+
+## Consequences
+
+**A seat is now the mesh's unit of "a role that talks".** A role that accepts work, announces outcomes
+or answers questions says so where it is defined, and everything about permissions, queues and
+consumers follows. Nothing hand-writes a grant for a role again.
+
+**The shared library cannot yet publish on a seat, and that is now the blocking gap rather than a
+curiosity.** A module holding a seat has the authority and no way to use it; the build machine is
+written in Go and reaches the bus directly, so it is unaffected, but the artifact-store event stays
+under its module's own name until the library has a surface for this. That is a task, and this record
+is what makes it one.
+
+**A second mechanism disappears.** `mesh.build.*`, the BUILDS stream and the builder's hand-written
+account all retire. Fewer things, and the ones left are derived.
+
+**The catch-up question is not settled by this**, only made answerable: a seat that serves something
+gives the controller a way to be asked, which the mesh did not have. Whether catch-up should be a
+question at all remains open.

02-DECISIONS/0130-the-predecessor-is-ending-and-its-broker-goes-with-it.md

@@ -0,0 +1,71 @@
+---
+topic: the mesh
+status: accepted
+date: 2026-09-27
+deciders: jochen
+reconstructed: false
+extends: 02-DECISIONS/0131-everything-on-the-mesh-speaks-to-the-broker-seat.md
+---
+
+# 130. The predecessor is ending, and its broker goes with it
+
+
+> **Pointer repointed, 2026-09-27.** This record was written extending
+> [ADR 0127](0127-amqp-is-a-provision-not-the-bus.md) (superseded by [ADR 0131](0131-everything-on-the-mesh-speaks-to-the-broker-seat.md)), which
+> [ADR 0131](0131-everything-on-the-mesh-speaks-to-the-broker-seat.md) has since superseded — AMQP is
+> not a provision at all. Nothing decided here changes; the frontmatter now rests on the live record,
+> and the citations below are read with that in mind.
+
+## Context
+
+[ADR 0127](0127-amqp-is-a-provision-not-the-bus.md) (superseded by [ADR 0131](0131-everything-on-the-mesh-speaks-to-the-broker-seat.md)) settled that the old broker is an ordinary
+provider of the `amqp` provision rather than a compatibility module with an end date. It rejected
+giving it a retirement condition, and said why: *"its clients are not only the predecessor's, so the
+retirement condition describes a day that will not come."*
+
+**The operator has said that day is coming.** The predecessor is deprecated. Some of it is still
+running, and it is not being migrated — it is being left to stop. Its broker may be shut down.
+
+That is a fact about this installation, not a change of mind about what a broker is. It is recorded
+because three documents reason from the premise it overturns:
+[design 25](../03-DESIGN/01-to-be/25-the-bus-on-nats.md) §5 and §9, and
+[design 28](../03-DESIGN/01-to-be/28-building-the-bus.md)'s closing note that the predecessor's world
+"does not need to move: its broker is the compatibility module until its last client is gone."
+
+## Decision
+
+**The predecessor's broker retires when nothing requires `amqp`, by being unassigned like any other
+provider.** No retirement condition, no end-date machinery, no special case — which is ADR 0127 being
+paid off rather than revised. Because that record made the broker an ordinary provider, ending it
+needs nothing that does not already exist: a provision with no consumers has its provider unassigned,
+and the module system has done that since it existed.
+
+**So step 5.3 has an ending.** "The mesh's own accounts removed from the deprecated broker" was
+written as the last thing that could be said, because the broker itself was going to outlive the
+question. It now finishes: once the mesh's own traffic has moved and the predecessor's remnants have
+stopped, the module is unassigned and the port is free.
+
+**And the transitional doubling has a date.** The build outcome is announced under both the module's
+name and the role's on the old bus, so that a catalogue deployed before the rename and one deployed
+after both hear it. That exists only while the old bus does, and goes with it.
+
+## Consequences
+
+**The remote access path goes with it, and that is the one practical consequence worth planning
+around.** The predecessor's own mesh communicates over that broker — so shutting it down ends the
+tooling that reaches this installation's machines remotely. Work on the node after that point is done
+from the node. **This matters most for the rollout**, which is the step that would otherwise be driven
+from a workstation: it has to be driven locally, or driven before the broker stops.
+
+**What is still running on it stops when it stops.** Some of the predecessor's services are live and
+are not being moved. That is the operator's decision and it is recorded here so that nobody later reads
+a broker with clients as an accident.
+
+**Nothing in a served request's path is affected.** Modules serve from their own containers; the mesh's
+bus carries the mesh's own traffic — declarations, reports, events, tool calls. This was checked rather
+than assumed when the question came up, and it is why the operator's position (*"as long as my services
+keep running"*) is a bounded risk rather than a gamble.
+
+**One reason to keep the broker survives**: `amqp` remains a provision a module may require, and a
+module that genuinely needs an AMQP broker can be given one. What retires is *this* broker's role as
+the predecessor's, not the mesh's ability to provide the thing.

02-DECISIONS/0131-everything-on-the-mesh-speaks-to-the-broker-seat.md

@@ -0,0 +1,94 @@
+---
+topic: the mesh
+status: accepted
+date: 2026-09-27
+deciders: jochen
+reconstructed: false
+supersedes: 0127-amqp-is-a-provision-not-the-bus.md
+---
+
+# 131. Everything on the mesh speaks to the broker seat, and AMQP is not a provision
+
+## Context
+
+[ADR 0127](0127-amqp-is-a-provision-not-the-bus.md) settled the old broker as an ordinary provider
+of an ordinary provision, `amqp`, kept for whatever wanted a message broker of its own. The day the
+bus moved was the day that framing was tested, and it failed in a way that took the control plane
+down for an evening.
+
+Three things came out of the wreckage. **The protocol had leaked into the seat's contract**: for a
+module to hold `mesh-broker`, it had to provide what the seat delivers, and what it delivered was
+`amqp` — so the module that will carry the bus on NATS could not hold the seat that names the bus,
+while the module the mesh was leaving could. **A consumer of `amqp` is not asking for AMQP.** The two
+modules requiring it wanted the mesh's messaging — to emit an event, to hear a topic — and named the
+wire protocol only because that was the word available. **And AMQP and NATS are not interchangeable
+at the wire.** A provision named after a protocol can only ever be answered by that protocol, so once
+the bus is NATS an `amqp` provision has one possible provider, and it is the thing being retired.
+
+The operator's position, stated during the outage: modules depend on the broker *seat*, not on a
+protocol; AMQP is obsolete as anything the mesh's core knows about; a module that depends on `amqp`
+is wrong; and everything should reach the mesh's bus and be able to emit events and consume topics
+through it.
+
+## Decision
+
+**A module that needs messaging uses the mesh's bus, and the mesh's bus is whatever holds
+`mesh-broker`.** Emitting an event and consuming a topic go through the sdk, which is handed the
+bus by the mesh with the module's own credential. No manifest names a wire protocol to get it.
+
+**`amqp` is neither a provision nor a requirement.** Registration refuses a manifest that provides
+it or requires it. The `mesh-broker` seat delivers `mesh-bus`, and its holder is the module that
+provides `mesh-bus` — today the nats module, and only it.
+
+**The old broker's module and the two modules that required it leave the catalogue.** They are
+removed, not converted: one was a proof that a grant worked end to end, the other forwards mail off a
+queue, and both are re-done against the bus if wanted, as new modules under this record.
+
+**The controller's AMQP transport is deleted once every node reports on the new bus**, and the
+switch that selects a transport goes with it — one bus, so nothing to select.
+
+The predecessor's own broker is outside the mesh and not this record's concern
+([ADR 0130](0130-the-predecessor-is-ending-and-its-broker-goes-with-it.md)): what the predecessor's
+tooling loses when it stops is accepted there.
+
+## Options considered
+
+1. **Keep 0127: AMQP stays an ordinary provision with the old broker as its provider.** Rejected. It
+   is what put the protocol into the seat's contract, it is why the seat could be left with no valid
+   holder mid-change, and it keeps two transports in the control plane indefinitely for the benefit of
+   two modules that did not want AMQP in the first place.
+2. **Bridge it: the old broker's module also provides `mesh-bus`, so both can hold the seat during the
+   change.** Rejected. It makes the retiring broker a legitimate mesh bus for exactly as long as
+   nobody removes the line, which in practice is forever, and it leaves `amqp` as a thing the core
+   still knows the name of.
+3. **The seat is the dependency; the protocol is nobody's business but the holder's.** Adopted.
+
+## Consequences
+
+- **The change of holder is a handover, and it needs a command.** Nothing today moves a seat from
+  one assignment to another as one act, and a seat the control plane dereferences cannot be empty
+  in between — that emptiness is the outage this record comes from. The command takes a seat and the
+  assignment taking it over. Designed and built before the cutover, under
+  [28 — Building the bus](../03-DESIGN/01-to-be/28-building-the-bus.md).
+- **The seat's row moves to `mesh-bus` before the new holder registers, and that is safe.** The
+  control plane composes its own bus address through the seat *by name*
+  (`${seat:mesh-broker:…}`), and the overview derives holders by name; only registration and the
+  provision-to-seat resolution read what a seat delivers. So the row can change under the current
+  holder without unseating it, the new holder can then register its claim, and the handover happens
+  when both are running. Verified in the code during the outage, not assumed.
+- **Registration gains two refusals**: a manifest providing `amqp`, and one requiring it.
+- **The `rollout check` stops saying the old broker stays.** It said so under 0127; it now lists
+  unassigning it as the last step of the move.
+- **What got harder**: a third party that genuinely wants an AMQP broker on a mesh node runs one as
+  any application module, with no provision and no seat, and nothing on the mesh routes to it. That
+  is the cost of the mesh not knowing the word.
+
+## How this is checked
+
+| Rule | Checked by |
+|---|---|
+| No manifest provides or requires `amqp` | a registration test refusing each, naming this record; and a whole-catalogue test asserting no registered manifest names it |
+| `mesh-broker` delivers `mesh-bus`, and only a `mesh-bus` provider may hold it | the existing registration test for a delivering seat, with the row's value read from the store (mesh-controller#89) |
+| The seat's row can change without unseating the holder | a test composing the control plane's own address and the overview under a row that the current holder does not satisfy |
+| The rollout does not leave the old broker running | `rollout check` output, asserted in its test |
+| The AMQP transport is gone | the package does not compile with it referenced; the switch variable is refused as unknown at start |

02-DECISIONS/0132-a-seat-carries-the-tools-its-holder-must-serve.md

@@ -0,0 +1,150 @@
+---
+topic: the mesh
+status: accepted
+date: 2026-09-28
+deciders: jochen
+reconstructed: false
+extends: 02-DECISIONS/0129-a-seat-carries-the-protocol-of-its-role.md
+---
+
+# 132. A seat carries the tools its holder must serve
+
+## Context
+
+[ADR 0129](0129-a-seat-carries-the-protocol-of-its-role.md) gave a seat the protocol of its role in
+three parts: the work it accepts, the events it emits, and the verbs it **serves** — request and
+reply, awaited. The bus already derives authority from all three: a holder subscribes
+`mesh.seat.<seat>.tool.<verb>`, and a module that uses the seat may publish it and nothing else.
+
+**The serving third has never been used.** The mesh defines 14 seats, 8 mesh-scoped and 6
+node-scoped. Exactly one carries a protocol at all — the build machine, which accepts `build` and
+emits `built`. Not one seat declares a single verb it serves. The mechanism is built, enforced, and
+empty.
+
+Meanwhile every tool on the mesh is addressed to a module. Of 72 modules in the catalogue, 45 serve
+tools, about 203 of them, each on `mesh.mod.<module>.tool.<name>`. So a caller binds to the module
+that happens to hold a role rather than to the role, and replacing that module breaks every caller —
+which is the thing seats exist to prevent everywhere else.
+
+**Nothing can say what tools exist.** Measured on 2026-09-28, with the bus carrying the whole mesh: a
+workstation client holding an operator credential connected, the bus accepted the account, and
+`mesh call gitea.gitea_list_repos` answered with real repositories. The same client's `mesh tools`
+found nothing, because it asks `mesh-catalog.catalog_tools` and no module serves that: the catalogue
+serves `catalog_modules`, `catalog_module`, `catalog_provides`, `catalog_dependents` and
+`catalog_stale`. An agent can therefore call any tool it already knows the name of and discover none.
+MCP's `tools/list` is that same question, so the MCP surface is a working transport over an empty
+catalogue.
+
+**And there is nowhere for a tool's definition to live.** A manifest has a `tools` field: 0 of the 45
+modules that serve tools fill it. That is not neglect, it is the arrangement failing — the field was
+the bus grant's source for what a module may subscribe, and because nothing filled it every module
+that served a tool was refused its own subscription on the new bus, live, until the grant was changed
+to the module's own namespace. Today a tool's name, description and argument schema exist only in the
+module's code.
+
+Two facts about the machinery matter for what follows. A seat's protocol is not in the store: the seat
+rows lack the ADR 0129 columns, so the protocol comes from compiled defaults and is merged in when a
+row is read. And `seatSubject` is flat — `mesh.seat.<seat>.<kind>.<verb>` with no node in it — so a
+node-scoped seat's tool call would reach every node's holder at once, and the holders' queue group
+would hand it to whichever answered first.
+
+## Decision
+
+**A seat's protocol carries its tools in full**: the verb, what it does, and the schema of its
+arguments and of its answer. The seat is the definition of the role's interface; the holder is an
+implementation of it.
+
+**Serving the seat's tools is a condition of holding the seat.** A module that does not serve every
+verb the seat declares may not occupy it. This is checked where the other conditions of holding are
+checked — registration and handover — and refused by naming the verbs that are missing.
+
+**A role's tools are addressed to the role.** `mesh.seat.<seat>.tool.<verb>` mesh-wide. A node-scoped
+seat carries the node in the address, because one subject reaching six machines' holders is not an
+address, and the queue group that made it look like one would silently pick a winner.
+
+**A module keeps its own tools, and both exist.** `gitea_list_repos` stays, because gitea can run
+without holding the `git` seat — a second forge, an instance kept for one purpose. The module's name
+answers *this gitea*; the seat's verb answers *whoever is the forge*. Which of the two a caller wants
+is a decision in the running session, not one the mesh makes for it.
+
+**What answers "what tools exist" follows where the definition lives.** A seat's tools are read from
+the mesh's own records. A module's own tools are answered by the module, from the code that defines
+them. Discovery is therefore a read for the durable half and a question to the running mesh for the
+free half.
+
+**A seat's tools are an interface, and change like one.** Additive within a version; a change that
+would break a caller takes the version token the subject already has room for (design 29 §8), and the
+two run side by side until nothing is bound to the old one.
+
+**The mesh's own verbs are the `mesh-controller` seat's tools.** `status`, `push`, `build`, `assign`
+and the rest are a role's interface, not a container's, and the audit point [ADR 0095](0095-the-control-plane-is-the-way-to-ask-a-module.md)
+asks for is the seat's holder.
+
+## Options considered
+
+1. **The manifest declares each module's tools.** Rejected. The list is then written twice — in the
+   manifest and in the code — and a schema in a manifest goes stale silently, which is the worst kind
+   of wrong for something an agent reads to decide what to call. It is also the arrangement that has
+   already failed once: the field exists, 0 of 45 modules fill it, and the grant that depended on it
+   refused every tool subscription on the mesh.
+2. **Every runtime answers an introspection call, and something aggregates them.** Rejected as the
+   shape for a role's tools, kept for a module's own. An aggregator needs permission to publish into
+   every module's namespace, which is a widening the mesh otherwise gives only to the control plane;
+   and the answer is only as available as the modules are, so a mesh whose catalogue cannot say what a
+   role answers while its holder is down cannot plan against it.
+3. **The control plane answers everything.** Rejected. It puts a tool surface on the control plane for
+   tools it does not implement, and makes discovery depend on the one component that must stay
+   answerable while it is itself being replaced. The mesh's own verbs are its to answer, and it answers
+   them as the holder of a seat.
+4. **Seats only; no module tools.** Rejected. Most modules hold no seat, and inventing a seat per
+   module to give its tools a home would dilute what a seat is: one holder of a role the mesh needs
+   exactly one of.
+
+## Consequences
+
+**One capability can have two names, deliberately.** A forge that holds the `git` seat answers both
+`mesh.seat.git.tool.list_repos` and `mesh.mod.gitea.tool.gitea_list_repos`. This is the one place the
+mesh accepts two names for one thing, because they are answers to different questions and the second
+one survives the module not holding the seat. The glossary rule stands everywhere else.
+
+**A seat becomes a contract to implement.** Adding a verb to a seat is a change every holder must
+make, and a claim that was valid becomes invalid until it does. That is the point, and it is also the
+reason a seat's tools should be few and durable while a module's own stay free.
+
+**Three prerequisites, none of them in place.** The seat's protocol must be in the store rather than in
+compiled defaults, or discovery reads a binary rather than the mesh. The protocol must become richer
+than a list of verbs, because a verb without a schema is not something an agent can call. And a
+node-scoped seat needs the node in its subject before any of its tools can exist.
+
+**Discovery becomes cheap for the half that matters.** What roles the mesh has and what each answers is
+a query, with no fan-out and nothing to be up. An agent's authority can then be role-shaped — *the
+forge's tools* — rather than a list of module-specific names that changes when a module is replaced.
+
+**The MCP surface belongs inside the mesh.** Once the tools are the mesh's own records, the thing that
+serves them to an agent is a module the mesh assigns to the machine where the agent sits, with a
+credential the mesh minted and authority derived from what it may call — not a program started by hand
+with a credential printed to a terminal.
+
+## How this is checked
+
+- **Holding is refused without the verbs.** The condition sits with the other conditions of holding a
+  seat, so registration and a handover both refuse a module that does not serve what the seat declares,
+  and the refusal names the missing verbs. A test per condition, as the other seat conditions have.
+- **The grant is derived from the seat, and already is.** A holder's subscription and a user's publish
+  come from the seat's protocol, so a verb nobody declared is a subject nobody may use, and a verb the
+  seat declares reaches exactly its holder. The golden composition of the bus's user list is the test
+  that keeps it honest.
+- **Discovery is a read, and is tested as one.** What the mesh answers for a seat's tools equals what
+  the seat's records declare — no call to a module in the path, so the test needs no running module.
+- **A node-scoped seat's subject carries its node**, checked by the same test that checks the subject
+  table: two nodes holding one node-scoped seat derive two addresses.
+
+## References
+
+- [ADR 0129](0129-a-seat-carries-the-protocol-of-its-role.md) — the protocol this widens
+- [ADR 0121](0121-a-system-seat-is-named-for-its-scope-and-modules-define-their-own.md) — the role, its work and its events
+- [ADR 0095](0095-the-control-plane-is-the-way-to-ask-a-module.md) — a tool call passes one process where an audit belongs
+- [ADR 0126](0126-a-module-declares-its-own-seats.md) — an event is addressed to its emitter, for the same reason a role's verb is addressed to its role
+- [`03-DESIGN/01-to-be/26-the-seats.md`](../03-DESIGN/01-to-be/26-the-seats.md) — how a seat is held and handed over
+- mesh-controller #116, #117, #118 — the grants as they now stand: a module serves its own namespace, the control plane may ask any tool
+- Measured 2026-09-28 on the live mesh: an operator credential calling a module's tool over the bus answers; `tools/list` finds nothing

02-DECISIONS/0133-a-module-owns-its-migrations-and-the-mesh-owns-when-they-run.md

@@ -0,0 +1,159 @@
+---
+topic: what runs on it
+status: superseded
+date: 2026-09-28
+deciders: jochen
+reconstructed: false
+extends: 02-DECISIONS/0052-a-step-that-runs-once-before-a-container.md
+superseded-by: 02-DECISIONS/0135-a-module-version-prepares-its-state-before-it-runs.md
+---
+
+# 133. A module owns its migrations, and the mesh owns when they run
+
+## Context
+
+On 2026-09-28 the mesh replaced its own control plane, through its own upgrade path, with a build
+carrying a migration. Nothing applied it. For the next three quarters of an hour every build the mesh
+made was refused by the store with one line — *column "built_contexts" does not exist* — which reached
+only whoever happened to be waiting on that build's reply. The images were built and published, so the
+registry filled with artifacts the mesh has no record of, and the overview went on reporting that every
+module was current ([issue 133](../04-ISSUES/133-the-control-planes-schema-is-migrated-at-birth-and-never-again/00-report.md)).
+
+The schema had been created once, at genesis, by an action in the foundation bundle. Nothing ran it
+again, through many updates of the control plane since.
+
+**The mechanism to do this right already existed and one module used it wrong.**
+[ADR 0052](0052-a-step-that-runs-once-before-a-container.md) makes a run-once container a step the host
+runs to completion before whatever the declaration places after it, and names migrating a schema as the
+case it exists for. Three facts about how it is used today:
+
+- The control plane's manifest had no step at all. The immediate fix was to write one by hand, and that
+  hand-written step repeats three environment variables and three volume mounts from the server
+  resource it precedes — six chances to drift from the thing it prepares.
+- Two other modules hand-write the same shape for the same reason: gitea's admin bootstrap and
+  mosquitto's dynsec seed, each repeating its sibling's image, environment and mounts. One of them
+  ends in `|| true`, which is a lock implemented as a shrug.
+- The catalogue module takes the other road: it migrates its own schema in its own code when it starts.
+  That failure mode is a crash loop rather than a stop — the catalogue restarted 338 times this
+  morning on an unrelated start-time failure, and nothing anywhere said the mesh's graph had a gap.
+
+**What the mesh already has, and what HAL needed stages for.** Ordering a provider before its consumer
+is `providersFirst`, which topologically orders a node's modules. Ordering within a module is
+declaration order, and a run-once container gates everything after it. Remembering that a step has
+already run is the digest of its declaration, recorded only after it exits 0
+([ADR 0018](0018-a-picture-is-read-from-what-runs.md)) — and the image is part of that digest, so a new
+build re-runs it. Three of the four things a stage system provides are therefore already here. The
+fourth — that a module has a schema at all — is the only thing missing.
+
+**Nothing in the catalogue ships a migrations directory.** Of 72 modules, none has one; the modules that
+migrate do it in their own code. So this is not a decision about where SQL files live. It is a decision
+about who runs them and when.
+
+**Two facts bound what is safely expressible.** A node converges toward its own declaration without
+waiting on any other node. And of the five modules that run on more than one machine today — dnsmasq,
+fail2ban, networking, networkmanager, sshd — not one wants a store; every module with a database is on
+exactly one machine.
+
+## Decision
+
+**A container may declare steps to run before it.** The same container, run to completion, with
+different arguments, in order, before it starts. The mesh derives the run-once resources from that
+declaration, so the image, the environment, the volumes, the network and the credentials come from the
+one place they are already described and cannot drift from it.
+
+**A module's migrations are the first user of this, and the module owns them entirely.** The SQL, the
+order, the idempotence, the lock, and which dialect it speaks. The mesh never learns that postgres and
+mssql differ, because it runs the module's own image with the module's own arguments against the
+module's own binding and requires exit 0. A module needing both stores runs one step that does both.
+
+**The mesh owns the moment, and the gate is the guarantee.** Whether a version may serve when its
+schema is not there yet is a deployment question, and the mesh is the only thing that can answer it,
+because the mesh is what starts the container. A step that fails stops the container it precedes, so
+a failed migration is a version that does not serve rather than a version serving against a store it
+does not match.
+
+**Per node, and there is no level.** The step runs wherever the module runs. A step that ran "once,
+somewhere" would leave every other machine with no gate at all, and additive migrations protect old
+code against a new schema, never new code against an old one. The cost is an obligation a migration
+runner already carries: a version table and a lock.
+
+**"Once, mesh-wide" is what holding a seat means.** A step that is not idempotent — seeding an
+account, sending a notice, taking a backup — belongs to a module that holds a seat, where the mesh
+already guarantees one holder, on record, handed over deliberately. That is the answer to the level
+question rather than a field that has to invent an election and keep it somewhere.
+
+**Migrations are forward-only and additive.** The step runs before the *new* container starts, so the
+old one is still running against the new schema for the length of the apply.
+
+**Declared, never inferred.** The control plane cannot see inside an image, so a module that ships
+migrations and declares no step is not refusable at registration; it breaks on its first upgrade. This
+record says so rather than implying a check that cannot exist.
+
+## Options considered
+
+1. **Each module migrates itself when it starts** — what the catalogue does today. Rejected: it turns a
+   schema failure into a crash loop instead of a stop, it is invisible in the declaration so nothing can
+   say the module even has a schema, and two machines running the module both migrate at start with
+   nothing sequencing them.
+2. **The mesh applies migrations itself**, with a driver and a version table per store — HAL's shape.
+   Rejected: the mesh would have to know one store type from another, hold another module's store
+   credentials, and reach a machine to use them, which [ADR 0005](0005-the-node-host.md) forbids. It is
+   also the reason that shape needs levels: something central has to decide where the once happens.
+3. **A hook lifecycle** — pre-build, post-build, pre-deploy, post-deploy. Rejected: there is no deploy
+   event here to hook. A declaration is a desired state applied in order and reconciled forever, so
+   "pre-deploy" is exactly "a step before this container", pre- and post-build are what a Dockerfile and
+   the artifact list already are, and "post-deploy" has no moment to name.
+4. **A hook level** — once per module, or once per module-node assignment. Rejected as a field, kept as
+   a property: see the decision. A once-per-module step needs cross-node ordering underneath it to be
+   safe, and a node converging without waiting on its neighbours is worth losing on purpose rather than
+   by accident.
+5. **Every module hand-writes its own run-once step** — the immediate fix for the control plane.
+   Rejected as the general answer: it duplicates the resource it precedes, in three places already, and
+   a hand-written step is one the next module forgets. Forgetting it is the fault this record exists
+   for.
+6. **Record a schema level per module in the store.** Rejected: gating makes the invariant true by
+   construction, so a level is a second account of the same fact and the first one to go stale.
+
+## Consequences
+
+**Three hand-written steps collapse into one line each**, and the control plane's own migrate step stops
+repeating its server's environment and mounts.
+
+**The catalogue's self-migration becomes the exception to remove.** One shape, and the mesh's own
+control plane is not an exception to it either.
+
+**A module on two machines with one shared store must lock.** Today none is, so this is an obligation
+stated before it is needed rather than discovered by two concurrent migrations.
+
+**There is still no readiness-gated step.** Only an action carries `verify`; a container has no health
+notion, so "run this once the service answers" remains unexpressible and seeding through a running
+service's API has no home. That is its own decision about a container's readiness, and this record does
+not make it.
+
+**Genesis keeps its own action.** At birth there is no control plane to derive anything from, which is
+what [ADR 0067](0067-genesis-is-a-pivot.md) already says about that moment.
+
+## How this is checked
+
+- **The composition carries the step.** A test on a node's composed declaration: every container that
+  declares steps before it is preceded by them, and the derived step's image, environment, volumes and
+  network equal the container's — so the two cannot drift, which is the failure the hand-written kind
+  has.
+- **A failed step stops what follows.** The host already refuses to go on past a run-once step that did
+  not exit 0; the test for that is extended to a derived one, so the gate is checked rather than
+  assumed.
+- **The mesh's own schema is covered by the same mechanism as everything else.** The control plane
+  declares its step in its own manifest, so the case that failed on 2026-09-28 is the case the test
+  covers.
+- **A module claiming a seat for a once-only step is checked where seats are checked** — the conditions
+  of holding, not a new mechanism.
+
+## References
+
+- [ADR 0052](0052-a-step-that-runs-once-before-a-container.md) — the step this extends
+- [ADR 0018](0018-a-picture-is-read-from-what-runs.md) — a digest is the record that something happened
+- [ADR 0005](0005-the-node-host.md) — the control plane decides and never touches a machine
+- [ADR 0067](0067-genesis-is-a-pivot.md) — why genesis does it differently, once
+- [issue 133](../04-ISSUES/133-the-control-planes-schema-is-migrated-at-birth-and-never-again/00-report.md) — the failure that produced this record
+- [`03-DESIGN/01-to-be/32-what-a-module-declares.md`](../03-DESIGN/01-to-be/32-what-a-module-declares.md) §6 — the lifecycle this sits in
+- Measured 2026-09-28: three hand-written run-once steps repeating their sibling's resource; 0 of 72 modules with a migrations directory; 5 modules on more than one machine, none of them wanting a store

02-DECISIONS/0134-the-mesh-says-what-it-applied.md

@@ -0,0 +1,126 @@
+---
+topic: the mesh
+status: accepted
+date: 2026-09-28
+deciders: jochen
+reconstructed: false
+---
+
+# 134. The mesh says what it applied
+
+## Context
+
+The pipeline is observable on the bus from a merge to an artifact, and modules already plug into it:
+the forge emits `pull.merged`, the build machine's seat emits `built`, the catalogue emits `registered`,
+`upgraded` and `rebuild-needed`, providers emit `postgres.database.provisioned` and its siblings. Things
+consume them today — the catalogue consumes `built`, each provider consumes its own provisioning events,
+model-usage consumes `*.usage.*`, the audit logger consumes `**`. Nothing had to be invented for any of
+that; subscribing *is* plugging in.
+
+**It goes dark at the moment it touches a machine.** A host applies a declaration and reports to the
+control plane on the control branch, which only the control plane may read — correctly, because a report
+carries what a machine is and enrolment travels the same way. So nothing on the mesh says *this machine
+now runs version Y of module Z*, or that it refused to, or why.
+
+What that cost on 2026-09-28, in one morning:
+
+- A build result the store refused was visible only to whoever was waiting on that build's reply. For
+  three quarters of an hour the mesh built things and recorded none of them, while the overview said
+  every module was current ([issue 133](../04-ISSUES/133-the-control-planes-schema-is-migrated-at-birth-and-never-again/00-report.md)).
+- A module crash-looping at start — 338 restarts — was found by reading a container's logs by hand.
+  Nothing on the bus said the mesh's graph had stopped learning.
+- A run-once step that fails now stops an upgrade by design ([ADR 0133](0133-a-module-owns-its-migrations-and-the-mesh-owns-when-they-run.md)),
+  and the same silence would cover it: the version simply would not appear.
+
+**And the one thing the control plane does emit is refused by its own account.** Answering a catalogue
+that asks to catch up, it publishes each recorded build under `mesh.mod.control-plane.event.…` — a
+module namespace for a module that does not exist. Its own permissions refuse it, so a catalogue that
+restarts gets nothing and keeps its gap. The control plane has facts to state and nowhere to state
+them.
+
+## Decision
+
+**The mesh emits the deploy half of the pipeline as facts on the bus.** What a machine now runs, and
+what it refused to run and why. Both are facts about the mesh doing its work, in the same form as every
+other fact on the bus, so anything that wants them subscribes the way the catalogue subscribes to
+`built`.
+
+**The control plane states them, as the holder of the `mesh-controller` seat.** Its facts live under the
+seat's own namespace, which is where a role's events belong
+([ADR 0121](0121-a-system-seat-is-named-for-its-scope-and-modules-define-their-own.md),
+[ADR 0129](0129-a-seat-carries-the-protocol-of-its-role.md)) and which survives the control plane being
+replaced. That is also what gives the catch-up replay a subject it may publish instead of an invented
+module namespace.
+
+**Emitted when what a machine runs changes, not on every convergence pass.** A host reconciles
+continuously and reports each time; a fact per pass would be a fact per minute per machine that says
+nothing. The report carries the declaration it applied and what changed, so the control plane has what
+it needs to speak only when there is something to say.
+
+**A refusal is a fact with a subject in it** — which machine, which resource, and the reason as the host
+gave it. A refusal that names only the machine is the silence this record is about, one level up.
+
+**Reports stay where they are.** A node's report remains control traffic that only the control plane
+reads. The deploy facts are derived from it, which makes them second-hand on purpose: one emitter, one
+ordering, and no widening of the narrowest account in the mesh.
+
+## Options considered
+
+1. **Leave it as it is, and let whatever cares ask the control plane.** Rejected: asking for a fact that
+   already arrives is the shape the mesh removed everywhere else, and nothing can react at the moment a
+   machine changes — which is exactly when a graph, an audit or an operator wants to know.
+2. **Each node emits its own facts.** Rejected: it widens every host's account to an event namespace, and
+   a host's authority is deliberately the narrowest in the mesh. Its report already reaches the one thing
+   that can speak for it.
+3. **Widen who may read the control branch.** Rejected: that branch carries what machines say *to* the
+   control plane, enrolment included. Widening its readers widens that too, for an unrelated reason.
+4. **A registry of deploy hooks** — something registers interest and is called. Rejected: an event is
+   already the mechanism; there is nothing to register, and a callback is an address the mesh spent
+   [issue 102](../04-ISSUES/102-an-address-recorded-at-genesis-or-build-does-not-follow-the-nodes-ports/00-report.md)
+   learning not to keep.
+5. **Put the facts on the node's own declaration stream.** Rejected: that stream is last-per-subject by
+   design, so a machine away for an hour gets exactly the current declaration and nothing older. A
+   history of what happened cannot live in a stream built to forget.
+
+## Consequences
+
+**The audit logger gets the deploy half for nothing**, because it consumes everything.
+
+**A failure becomes visible where the mesh is watched** rather than where someone happened to be
+looking. That answers the open question [issue 133](../04-ISSUES/133-the-control-planes-schema-is-migrated-at-birth-and-never-again/00-report.md)
+left about a record the store refused.
+
+**The catch-up replay stops being a burst of events.** With the control plane able to state its own
+facts, replaying history as if it were happening now is a choice rather than the only option — and the
+better shape is the question the catalogue is actually asking, answered once
+([design 33](../03-DESIGN/01-to-be/33-the-tools-the-mesh-answers.md)).
+
+**The facts are second-hand.** The control plane says what a machine reported, so a machine that cannot
+reach the bus produces no fact at all. Absence is not health, and what a machine was last heard from
+stays the place that says so.
+
+**The events stream carries more.** Bounded by emitting on change rather than on every pass, and each
+fact is small; the stream's own limits remain what keeps it finite.
+
+## How this is checked
+
+- **The control plane's grant names exactly the subjects it emits**, derived from its seat like every
+  other principal's, and the composed user list is compared against a golden file — so a fact it cannot
+  publish fails a test rather than a catalogue's replay.
+- **A convergence that changed nothing emits nothing.** A test with two identical reports and one
+  expected fact, because the failure this guards against is a fact per minute per machine.
+- **A refusal names its resource.** A test where a host reports a failed resource and the emitted fact
+  carries which one and why, not merely that something went wrong.
+- **What the mesh emits is what something consumes.** The subject a module declares it consumes derives
+  to the subject the control plane publishes — the same agreement test that already keeps the
+  controller's own subscriptions honest.
+
+## References
+
+- [ADR 0041](0041-events-are-a-relationship.md) — an event is a relationship, not a call
+- [ADR 0126](0126-a-module-declares-its-own-seats.md) — an event is addressed to its emitter, because the emitter's identity is the meaning
+- [ADR 0121](0121-a-system-seat-is-named-for-its-scope-and-modules-define-their-own.md), [ADR 0129](0129-a-seat-carries-the-protocol-of-its-role.md) — a role's events belong to the role
+- [ADR 0083](0083-one-push-leaves-the-mesh-consistent.md) — a report is held for the store rather than lost
+- [ADR 0133](0133-a-module-owns-its-migrations-and-the-mesh-owns-when-they-run.md) — the gate whose failure this makes visible
+- [`03-DESIGN/01-to-be/32-what-a-module-declares.md`](../03-DESIGN/01-to-be/32-what-a-module-declares.md) §6 — the lifecycle, which ends today at a report nobody else may read
+- Measured 2026-09-28: 45 minutes of builds recorded nowhere with the overview reporting health; a module at 338 restarts found by hand; the control plane's only emitted event refused by its own permissions

02-DECISIONS/0135-a-module-version-prepares-its-state-before-it-runs.md

@@ -0,0 +1,153 @@
+---
+topic: what runs on it
+status: accepted
+date: 2026-09-28
+deciders: jochen
+reconstructed: false
+supersedes: 0133-a-module-owns-its-migrations-and-the-mesh-owns-when-they-run.md
+---
+
+# 135. A module version prepares its state before it runs
+
+## Context
+
+[ADR 0133](0133-a-module-owns-its-migrations-and-the-mesh-owns-when-they-run.md) settled who runs a
+module's migrations and when, and it said so in the wrong vocabulary. It put the declaration on a
+*container* — "a container may declare steps to run before it" — and derived the scope of the work from
+the *machine*. Both are wrong at the level a module author works at, and the second is wrong on the
+facts.
+
+**A container is one resource kind the host applies.** A module has code, state and a version; whether
+its artifact is an image, a bundle or something later is the mesh's business. The module-facing
+vocabulary for a module's own code already exists and has nothing to do with a container runtime: a
+module declares **entrypoints** — this file is my tools, this file is my provisioner — and the mesh runs
+them. A manifest that says "run this container with these arguments, and here are the volumes and
+environment again" has an author writing down the machine's business twice.
+
+**And the scope is not the machine's to decide, because the mesh already decided what a state is.** A
+consumer is a module *on a machine* (migration 0015, from
+[issue 022](../04-ISSUES/022-one-credential-per-node-per-provision-not-per-module/00-report.md)):
+the mesh derives a login per consumer and the provider creates a database owned by exactly that login
+([ADR 0048](0048-a-provider-creates-the-credential-the-mesh-minted.md)). So a module on three machines is three
+consumers, three credentials and three databases. There is no shared state for two machines to race over,
+and ADR 0133's central caveat — that a module's migrations must take a lock because two machines might
+migrate at once — describes a situation the mesh does not currently produce.
+
+That correction makes the whole "level" question HAL answered with stages disappear: the scope of
+preparation is the scope of the state, and the mesh knows it.
+
+What the earlier record got right and this one keeps: the module owns the work, the mesh owns the moment,
+the gate is the guarantee, migrations stay forward-only, and none of it can be inferred from inside an
+artifact. What produced it also stands — the control plane was replaced with a build carrying a migration,
+nothing applied it, and for three quarters of an hour every build was refused by the store with one line
+that reached only whoever was waiting on a reply
+([issue 133](../04-ISSUES/133-the-control-planes-schema-is-migrated-at-birth-and-never-again/00-report.md)).
+
+## Decision
+
+**A module version declares an entrypoint that prepares its state.** One name in the manifest, in the
+same vocabulary as the entrypoints it already declares for its tools and its provisioner. No container,
+no command line, no environment, no mounts — those are how a machine runs the module's code, and the
+module already said that once.
+
+**The mesh runs it as it runs that module's own code, to completion, in the module's own context.** Every
+binding, credential and setting the module's code would receive, because it *is* the module's code. How a
+machine does that is the host's business and stays there: for an image artifact it is the step
+[ADR 0052](0052-a-step-that-runs-once-before-a-container.md) already defines, and a later kind of artifact
+changes the host, not the manifest.
+
+**Preparation gates the version.** A version whose preparation did not succeed does not run — anywhere.
+Since the rollout already sends machines one at a time and stops at the first that does not take a
+version, a preparation that fails stops the rollout there, leaving every other machine on the version
+that works.
+
+**Preparation is scoped to the state, and the mesh derives that scope.** State the mesh provisions is per
+consumer — a module on a machine — so preparation happens once per consumer. State the module keeps on
+the machine is per machine, which is the same answer. A module that holds an exclusive seat has one of
+itself, so its preparation happens once by definition. No level, no election, no cross-node ordering, and
+no lock obligation invented for a race the mesh does not create.
+
+**Once per version per state.** A version bump attempts preparation once against each state it has; the
+module's own runner decides there is nothing to do, which is what a runner with a version table does
+anyway. A retry after a partial failure runs it again, so the work is the module's to make safe against
+that — the one obligation no design can remove.
+
+**Forward-only and additive.** Preparation runs while the previous version is still serving, so a
+migration that removes or renames what the old code reads breaks the mesh in the window between the two.
+
+**Declared, never inferred.** The control plane cannot see inside an artifact, so a module that ships
+migrations and declares no entrypoint is not refusable at registration. It breaks on its first upgrade,
+and this record says so rather than implying a check that cannot exist.
+
+## Options considered
+
+1. **A container declares steps before it** — [ADR 0133](0133-a-module-owns-its-migrations-and-the-mesh-owns-when-they-run.md).
+   Superseded, not because the mechanism is wrong but because the *declaration* is in the wrong place: it
+   makes every module author restate the machine's arrangement, and it ties a module's own lifecycle to
+   one resource kind. The host-side mechanism it named is retained and is now an implementation detail.
+2. **Each module prepares itself when it starts** — what the catalogue does today. Rejected: a schema
+   failure becomes a crash loop rather than a stop, nothing in the declaration says the module has a
+   state to prepare, and the version serves the moment it starts rather than after the state is right.
+3. **The mesh applies migrations itself**, with a driver and a version table per store type. Rejected:
+   the mesh would have to know one store from another, hold another module's credentials and reach a
+   machine with them, which [ADR 0005](0005-the-node-host.md) forbids. It is also what forces a stage
+   system: something central has to decide where the work happens.
+4. **A hook lifecycle** — pre-build, post-build, pre-deploy, post-deploy. Rejected: a declaration is a
+   desired state reconciled forever, so there is no deploy moment to hook. "Pre-deploy" is exactly this
+   record; pre- and post-build are what a recipe and the artifact list already are; "post-deploy" names
+   nothing that happens.
+5. **A declared level** — once per module, or once per assignment. Rejected: the mesh already knows what a
+   state is, so asking an author to choose is asking them to restate a fact the mesh holds, with a chance
+   of contradicting it.
+6. **Record a preparation level per module in the store.** Rejected for the reason ADR 0133 gave and this
+   record keeps: gating makes the invariant true by construction, and a level is a second account of the
+   same fact.
+
+## Consequences
+
+**An author's whole contract is one line, once.** Write the migration in the module's code, name the
+entrypoint that runs it, and every later version rolls out as: build, prepare, run — with nothing
+per-version to remember and nothing about the machine to restate. That is the property this exists for.
+
+**Three hand-written steps in the catalogue collapse**, and the control plane's own migrate step stops
+repeating its server's environment and mounts.
+
+**The catalogue's self-preparation becomes the exception to remove.** One shape, and the mesh's own
+control plane is not an exception either.
+
+**A module scaled across machines with one shared state is not expressible**, and this record does not
+make it so. The mesh gives each consumer its own state; a deliberately shared one is a different
+provision model, and the place the "once, mesh-wide" question would genuinely return. Named here so it is
+a decision when it happens rather than a surprise.
+
+**There is still no readiness-gated step.** Only an action carries `verify`; nothing declares that a
+service answers, so preparation that must happen *after* something is serving — seeding through its own
+API — remains unexpressible.
+
+**Genesis keeps its own action.** At birth there is no control plane to derive anything, which is what
+[ADR 0067](0067-genesis-is-a-pivot.md) says about that moment.
+
+## How this is checked
+
+- **The composition carries the preparation, in the module's own context.** A test on a node's composed
+  declaration: a version declaring a preparation entrypoint is preceded by it, and what it is given
+  equals what the module's own code is given — asserted equal rather than written twice, which is the
+  drift the superseded shape invited.
+- **A preparation that fails stops the version.** The host does not go past a step that did not complete,
+  and the rollout stops at the first machine that did not take a version. Both are existing behaviours
+  with existing tests; the test for preparation asserts the two together — the machine does not run it,
+  and the machines after it are left alone.
+- **Once per version per state.** A test that a second convergence of the same version prepares nothing,
+  and that a new version prepares again.
+- **The mesh's own control plane declares one.** The case that failed on 2026-09-28 is the case the tests
+  cover, rather than a case a comment says is covered.
+
+## References
+
+- [ADR 0133](0133-a-module-owns-its-migrations-and-the-mesh-owns-when-they-run.md) — what this supersedes, and why
+- [ADR 0052](0052-a-step-that-runs-once-before-a-container.md) — the host-side step that implements it for an image artifact
+- [ADR 0048](0048-a-provider-creates-the-credential-the-mesh-minted.md), [issue 022](../04-ISSUES/022-one-credential-per-node-per-provision-not-per-module/00-report.md) — a consumer is a module on a machine, which is what makes the scope derivable
+- [ADR 0018](0018-a-picture-is-read-from-what-runs.md) — a digest is the record that something happened
+- [ADR 0005](0005-the-node-host.md) — the control plane decides and never touches a machine
+- [ADR 0134](0134-the-mesh-says-what-it-applied.md) — what makes a failed preparation visible
+- [issue 133](../04-ISSUES/133-the-control-planes-schema-is-migrated-at-birth-and-never-again/00-report.md) — the failure that produced both records

02-DECISIONS/0136-a-step-gates-its-module-not-the-machine.md

@@ -0,0 +1,106 @@
+---
+topic: what runs on it
+status: accepted
+date: 2026-09-28
+deciders: jochen
+reconstructed: false
+extends: 02-DECISIONS/0052-a-step-that-runs-once-before-a-container.md
+---
+
+# 136. A step gates its module, not the machine
+
+## Context
+
+[ADR 0052](0052-a-step-that-runs-once-before-a-container.md) made a run-once container a step the host
+runs to completion, and gave it the same reach a failed action has: it stops everything the declaration
+places after it. When the only steps on the mesh were a broker's seed and a forge's admin account, that
+reach was invisible — the thing after the step was the container the step existed for, in the same
+module.
+
+[ADR 0135](0135-a-module-version-prepares-its-state-before-it-runs.md) made a step something the mesh
+derives for **any** module that prepares its state, and that turns the reach into a fault. A module
+whose database is briefly unreachable now stops every module declared after it on that machine, for as
+long as it is unreachable.
+
+**The host already rejected this for every other shape, and says why in its own loop.** From
+[issue 011](../04-ISSUES/011-one-broken-module-blocks-every-other/00-report.md):
+
+> It used to stop at the first one, and that made one broken resource hold the whole machine hostage: a
+> module declaring a package that does not exist meant every module ordered after it was never applied,
+> for ever, and the mesh reported "failed" without saying that the rest had not been tried. A machine
+> with one bad module and nine good ones ran none of the nine.
+
+Everything is attempted and every failure reported — except an action and a run-once step, kept as the
+deliberate exceptions. So the mesh has two rules about the same question and the wider one is now
+reachable by any module that declares a schema.
+
+**And it deadlocks a case the catalogue already named.** The catalogue migrates its own schema when it
+starts rather than in a step, and says why in its code: *a schema step that had to reach the provider
+over the overlay would block the very apply that brings the overlay up*. With a machine-wide gate that
+is exactly right — the step fails, the apply stops, the overlay module after it is never applied, and
+the next reconcile is blocked the same way. The module that most obviously wants a step could not have
+one.
+
+## Decision
+
+**A step gates its own module.** A run-once container that does not complete stops the rest of *that
+module's* resources and nothing else. Every other module on the machine is attempted, as every other
+shape already is.
+
+**An action still gates the machine.** Genesis is a row of actions, each making the next possible, and
+they belong to no module — there is nothing narrower for their reach to be.
+
+**What was not attempted is reported, not inferred from silence.** A skipped resource appears in the
+machine's account of the apply as skipped, with the reason, because "not attempted" and "nothing to do"
+are different answers and only one of them is somebody's to fix.
+
+**A module is the part of a resource's identity before the first dot**, which is how the mesh composes
+them. What the mesh declares in its own right — a guard, an opening, the adoption's own resources —
+belongs to no module, and its gate is therefore the machine's.
+
+## Options considered
+
+1. **Leave the reach as it is.** Rejected: it reintroduces, through a mechanism now derived for every
+   module, exactly the fault issue 011 removed. A mesh where one module's unreachable database stops a
+   machine converging is worse than one where that module alone is behind.
+2. **Make preparation not a gate at all** — run it and carry on. Rejected: then a version serves against
+   a state nobody shaped, which is the whole of what ADR 0135 exists to prevent.
+3. **Order every module's step before everything else on the machine**, so a gate stops nothing that
+   matters. Rejected: it inverts the order a module needs — its files and directories are declared before
+   its step because the step reads them — and it would still stop later modules.
+4. **Let a module declare how far its step reaches.** Rejected: the answer is the same for every module,
+   and a field would let one be wrong about it.
+
+## Consequences
+
+**The catalogue can move to a step.** The reason it migrates at start — that a step blocks the apply
+that would make its provider reachable — stops being true: the step fails, that module waits, the
+overlay comes up, and the next reconcile prepares it. One shape for the whole mesh, which is what
+ADR 0135 asked for and could not have had.
+
+**A module can sit behind while the machine is otherwise current.** That is the honest state and it is
+what the report now says. It also means a preparation that never succeeds is a module that never
+upgrades, quietly, until somebody reads the report — which is an argument for
+[ADR 0134](0134-the-mesh-says-what-it-applied.md) rather than against this.
+
+**A module's resources must be ordered within the module for the gate to mean anything.** They already
+are: the mesh composes a module's resources in the order its manifest declares them, and its own
+workload comes after the files it reads.
+
+## How this is checked
+
+- **A failed step stops its module and nothing else.** A test with two modules: the one whose step
+  failed does not start its workload, the other starts, and the error still says the failure gated
+  something. It fails against the previous behaviour, which is how it was written.
+- **An action still stops the machine.** The existing test for a failed action is unchanged, and a step
+  with no module in its identity — which is what genesis carries — takes the same path.
+- **The report names what was skipped.** Asserted in the same test, because a gate nobody can see is
+  indistinguishable from a module that had nothing to do.
+
+## References
+
+- [ADR 0052](0052-a-step-that-runs-once-before-a-container.md) — the step this narrows
+- [ADR 0135](0135-a-module-version-prepares-its-state-before-it-runs.md) — what made the reach reachable
+- [issue 011](../04-ISSUES/011-one-broken-module-blocks-every-other/00-report.md) — the same fault, removed once already
+- [ADR 0134](0134-the-mesh-says-what-it-applied.md) — how a module left behind becomes visible
+- mesh-host `internal/apply` — the loop whose own comment argued this case for every other shape

02-DECISIONS/0137-a-machine-says-which-networks-it-routes.md

@@ -0,0 +1,117 @@
+---
+topic: what runs on it
+status: superseded
+date: 2026-09-28
+deciders: jochen
+extends: 02-DECISIONS/0100-a-node-in-use-is-adopted-before-it-is-converged.md
+reconstructed: false
+superseded-by: 02-DECISIONS/0140-the-filter-constrains-what-arrives-from-outside.md
+---
+
+# 137. A machine says which networks it routes
+
+## Context
+
+The filter the mesh derives denies forwarding by default, because without a forward chain it says
+nothing about a container's published port
+([ADR 0100](0100-a-node-in-use-is-adopted-before-it-is-converged.md), [issue 047](../04-ISSUES/047-the-firewall-does-not-cover-published-container-ports/00-report.md)).
+To keep a machine's own containers working it then allows two ranges: the container runtime's
+default bridge pool, and the pool its compose files are given. Those two are named in the
+controller's code, with a comment saying what the gap is:
+
+> A machine whose runtime is configured with something else needs this to say so — which is a thing
+> the mesh cannot derive and a reason this list is named here rather than computed.
+
+**There was no way to say so.** The list was a constant. A machine whose guests live anywhere else
+was filtered by a rule that looked deliberate and was a guess.
+
+**Measured, on the day a workstation was converged.** Flipping it cut egress for five of its
+container networks at once, and for every network its test beds create — the beds allocate a fresh
+range per run, from a pool neither default covers. Nothing reported a fault. The containers could
+not reach anything, the machine went on reporting that it had applied what it was told, and the
+converge preview had said nothing about it either, because the preview lists what *listens* and
+routing is not a listener.
+
+**And two questions, not one.** A guest also asks its host for an address and for names. Both arrive
+at the input chain, where nothing declared them, so denying by default left the guests of a routed
+network with no address and no resolution — which is not a closed port but a network that does not
+function, asked for by this machine's own guest.
+
+**Why the machine cannot simply be read.** A test bed creates its bridge while it runs, between one
+declaration and the next, so a filter derived from what the machine last reported would be correct
+only for the networks that already existed when it was composed. A declared range covers the ones
+that do not exist yet.
+
+## Decision
+
+**A machine says which networks it routes for what it hosts, and the filter forwards them.** A
+node-level fact, beside the node's public domain
+([ADR 0066](0066-public-routing-is-name-agnostic.md)) and for the same reason: the
+machine routes them, and the module that loads the filter holds a seat and may be replaced.
+
+**Added to the runtime's defaults, never replacing them.** A machine that names one range has not
+stopped hosting whatever was already on the runtime's own pools, and replacing would trade one
+silent breakage for another.
+
+**Their guests keep address and name service.** For a network that was named, the input chain admits
+that network's own DHCP and DNS, and nothing else: everything else a guest might want from its host
+is a port somebody declares, like every other port on this machine.
+
+**Said in CIDR form and checked when it is said.** An entry that does not parse is a line nftables
+refuses, and a refused ruleset is a machine filtering nothing while its unit reports a fault — so
+the refusal happens where a person can read it, not on the machine.
+
+**A machine that says nothing is filtered exactly as before.** Every machine already converged is
+untouched by this.
+
+## Options considered
+
+1. **Leave it constant and edit the code per installation.** Rejected: the value is a property of
+   one machine, the code is the whole mesh's, and the two ranges as they stand describe a machine
+   whose runtime was left at its defaults. It is also how this got here.
+2. **Derive it from what the machine reports.** Rejected as insufficient, not as wrong: it cannot
+   cover a network created between two declarations, which is precisely the case that was broken. It
+   would also make the filter follow whatever appeared on the machine, which is a firewall that
+   widens itself.
+3. **A per-node setting on the module that loads the filter.** Rejected: the machine routes the
+   networks. The filter module holds a node-scoped seat and is meant to be replaceable, and a
+   replacement must not lose the machine's own truth.
+4. **Replace the defaults with what is said.** Rejected: see the decision. The first machine to name
+   its bed range would lose its containers.
+5. **Admit all input from a routed network, not only address and name service.** Rejected: that is
+   every port on the machine open to anything it hosts, which is the derivation abandoned.
+
+## Consequences
+
+**The converge preview says what a machine routes**, including when it routes nothing but the
+defaults, with the command that changes it. The preview's own sentence about traffic it cannot
+preview stays, because a tunnel and the found firewall's NAT are still not previewable.
+
+**A machine whose guests are already broken by an earlier flip is fixed by saying its networks and
+pushing**, with no flip to undo.
+
+**The list is one more thing that can be wrong and stale.** A range removed from the machine and
+left here keeps forwarding for a network that no longer exists, which admits nothing, because there
+is no guest on it to admit. That is the safe direction of being out of date.
+
+## How this is checked
+
+- **What a machine says it routes is forwarded, and its guests keep address and name service.** A
+  test renders a ruleset for a machine that names one range and asserts both chains, per chain body
+  so a line in the wrong chain cannot pass it. It fails against the previous behaviour, which is how
+  it was written.
+- **The runtime's own defaults survive naming a range.** Asserted in the same test.
+- **A machine that names nothing renders byte-identically to one that names nil**, so every machine
+  already behind this filter is untouched.
+- **Each family is matched in its own syntax.** A test with one v4 and one v6 network asserts
+  `ip saddr` and `ip6 saddr`, because one set holding both is a syntax error and a ruleset that does
+  not load is a machine filtering nothing.
+- **An entry that is not a network is refused where it is said**, by the parse in the setter.
+
+## References
+
+- [ADR 0100](0100-a-node-in-use-is-adopted-before-it-is-converged.md) — the derived filter this completes
+- [ADR 0066](0066-public-routing-is-name-agnostic.md) — the precedent for a node-level fact
+- [issue 047](../04-ISSUES/047-the-firewall-does-not-cover-published-container-ports/00-report.md) — why there is a forward chain at all
+- [issue 137](../04-ISSUES/137-converging-a-machine-cut-off-its-own-guests/00-report.md) — the measurement that produced this
+- mesh-controller `internal/catalogue/filtering.go` — the constant whose own comment named this gap

02-DECISIONS/0138-an-assignment-binds-an-endpoint-and-says-how-far-it-reaches.md

@@ -0,0 +1,154 @@
+---
+topic: what runs on it
+status: accepted
+date: 2026-09-28
+deciders: jochen
+reconstructed: false
+extends: 02-DECISIONS/0045-a-machine-firewall-is-the-sum-of-what-it-listens-on.md
+---
+
+# 138. An assignment binds an endpoint and says how far it reaches
+
+## Context
+
+[ADR 0045](0045-a-machine-firewall-is-the-sum-of-what-it-listens-on.md) settled that a machine's
+packet filter is derived from what its modules declare they listen on, and that the `from` of a
+listen "is the whole of public-versus-internal". That was true of the packet filter, and it turned
+out to be true of nothing else.
+
+Reachability is now settled three times, in three places, by three mechanisms that cannot disagree
+out loud ([issue 140](../04-ISSUES/140-an-endpoints-reach-is-not-declared/00-report.md)):
+
+- **The filter** reads a listen's source, and a per-node setting may override it. That setting has
+  exactly one caller in the control plane — the function that builds the node's rules.
+- **The names** come from a route contribution, which names a label and a port and says nothing
+  about reach. The reverse proxy composes a **public** name and an **internal** name for every route
+  it is given, because it can.
+- **The certificate authority** follows from which names exist. Measured on the control-node: an
+  identity provider carries a public certificate valid 90 days and an internal one valid 24 hours and
+  renewed daily. No assignment asked for either.
+
+So *this endpoint must not be public* cannot be written. It is therefore enforced by nothing, while a
+public certificate for that very name is obtained automatically — the fault
+[how-we-build.md](../00-META/how-we-build.md) names, an unenforced rule being indistinguishable from
+a wrong one, with the additional cost that the wrong thing is done eagerly.
+
+And a port that is not routed cannot be spoken about at all beyond the filter. The forge serves git
+over ssh; that endpoint has no name, no certificate and no way to be called public except a key only
+the filter reads.
+
+**Two per-node settings already exist and are half of this.** One gives a module's declared port a
+machine port. One overrides a declared port's source. They key on port numbers, so nothing ties a
+port to the route that serves it: a route contribution names a port too, and the two are equal only
+by coincidence.
+
+**Where this belongs is already decided.** [ADR 0046](0046-a-module-configuration-is-its-assignments-not-its-manifest.md)
+says a module's configuration is its assignments. Whether the forge answers git-over-ssh from the
+public internet is a fact about one installation and one machine, not a property of the software —
+and [ADR 0112](0112-a-module-definition-names-no-node-mesh-or-path.md) already refuses an
+installation's decisions in a definition.
+
+## Considered Options
+
+1. **Leave reach in the manifest, as `from` today.** Rejected: it is an installation's decision
+   written into the definition, and it cannot differ between two machines running the same module —
+   which is exactly the case the forge presents.
+2. **Extend the existing source override to the names and the certificate, without naming
+   endpoints.** Rejected: it keys on a port number. A module's route contribution names a port as
+   well, and nothing says the two are the same thing, so one statement cannot be made to reach all
+   three mechanisms. Naming the endpoint is what makes that possible.
+3. **Derive reach from whether the node has a public domain recorded.** Rejected: that is a property
+   of the machine, and two endpoints on one machine differ — a database and a web front end on the
+   same host.
+4. **A fourth reach for "public name, internal authority"** — a name that resolves publicly and must
+   not appear in a public issuance log, obtained by DNS-01. Deferred, not rejected: it is a real case
+   and it is a question about which challenge an authority uses, not about how far an endpoint
+   reaches. Left to the certificate work as an open question.
+5. **Make the manifest silent on reach and require every assignment to state it.** Rejected for the
+   transition: every endpoint reachable today would close until an assignment named it, which is a
+   flag day across the whole catalogue.
+
+## Decision
+
+**A module declares named endpoints.** An endpoint is one port the module serves, with a name the
+module chooses, its protocol, and what it is for. A route contribution **names the endpoint it
+routes** rather than repeating a port number. The manifest says what the module serves and what it
+would serve it to by default; it does not say what this installation does with it.
+
+**An assignment binds each endpoint and says how far it reaches.** Per node: the machine port the
+endpoint is published on, and its **reach** — one of `internal`, `public` or `both`. An assignment
+that states nothing keeps the manifest's default, so no machine changes until an assignment says so.
+
+**Reach means all three mechanisms at once, and is the only thing that decides them.**
+
+- `internal` — the filter opens the machine port to the private network; the proxy serves the
+  internal name and not the public one; the certificate comes from the mesh's own authority.
+- `public` — the filter opens it to anywhere; the proxy serves the public name; the certificate
+  comes from the public authority.
+- `both` — both names, each from its own authority, and the filter opens to anywhere.
+
+**An endpoint that is not routed is reached but never named.** An endpoint with no route contribution
+yields filter rules and nothing else: no name is composed and no certificate is requested. Git over
+ssh is that case, and it is the case the model could not express.
+
+**The authority stops being chosen by which names happen to exist.** The proxy composes the names the
+assignments asked for, and asks each name's own authority for it. A name nobody asked for is not
+composed, so it is not certified.
+
+**The two existing settings are this, completed.** The per-node port mapping becomes the endpoint's
+binding. The per-node source override becomes its reach, widened from the filter alone to the names
+and the certificate as well.
+
+## Consequences
+
+- **A manifest gains endpoint names, and a route contribution names an endpoint instead of a port.**
+  Every routed module's manifest changes. The word ships one release before any manifest uses it, and
+  reaches the build machine and the control plane first.
+- **One derived value is read by three things** — the filter's rules, the proxy's contributions, the
+  certificate request — so they can no longer disagree, and a disagreement becomes a refusal at the
+  assignment rather than a surprise on a machine.
+- **A name that must not be public becomes writable, and therefore checkable.** It also gives
+  [issue 129](../04-ISSUES/129-nothing-makes-a-machine-trust-the-meshs-authority/00-report.md) a
+  declared answer to read: which endpoints are internal is what says whose root must be installed
+  where.
+- **[Issue 139](../04-ISSUES/139-an-internal-route-name-resolves-to-the-consumers-node/00-report.md)
+  becomes answerable**: the endpoint's assignment names the machine that serves it, which is the fact
+  the internal name should be composed from.
+- **Reach becomes reportable.** The mesh can say, per endpoint, where it is reachable from and which
+  authority holds its certificate — neither of which `status` can say today.
+- **This narrows [ADR 0045](0045-a-machine-firewall-is-the-sum-of-what-it-listens-on.md).** Its
+  decision stands: the firewall is derived and host-applied, not a provider. What no longer holds is
+  that a listen's `from` is the whole of public-versus-internal; it is the filter's share of a
+  statement that also governs names and certificates.
+- **What got harder:** every endpoint needs a name, including a module that serves exactly one port
+  and had no reason to name it. And an installation that wants a module public must now say so on the
+  assignment rather than inheriting it from the definition, which is more to say and the reason it is
+  right.
+
+## How it is checked
+
+- **One module, two endpoints, different reach.** A module declaring an internal endpoint and a
+  public one renders a filter opening one to the private network and one to anywhere, asserted per
+  chain body so a rule in the wrong chain cannot pass.
+- **The names follow the reach.** The same module's routed endpoint composes the internal name only
+  when internal, the public name only when public, and both when both — and a certificate is
+  requested from the matching authority for each name composed and for no other. This fails against
+  the previous behaviour, where both names and both certificates are always composed, which is how
+  it is written.
+- **An unrouted endpoint is filtered and never named.** Asserted for an endpoint with reach and no
+  route contribution: rules rendered, no contribution, no certificate request.
+- **An assignment naming an endpoint the module does not declare is refused where it is said**, as is
+  a reach that is not one of the three — before it reaches a machine, because a ruleset that does not
+  load is a machine filtering nothing.
+- **An assignment that states nothing renders byte-identically to today**, so every machine already
+  converged is untouched until its assignment says otherwise.
+
+## References
+
+- [ADR 0045](0045-a-machine-firewall-is-the-sum-of-what-it-listens-on.md) — narrowed here
+- [ADR 0046](0046-a-module-configuration-is-its-assignments-not-its-manifest.md) — where reach belongs
+- [ADR 0066](0066-public-routing-is-name-agnostic.md) — the public name this composes
+- [ADR 0112](0112-a-module-definition-names-no-node-mesh-or-path.md) — why reach is not a definition's
+- [issue 140](../04-ISSUES/140-an-endpoints-reach-is-not-declared/00-report.md) — the measurement
+- [issue 139](../04-ISSUES/139-an-internal-route-name-resolves-to-the-consumers-node/00-report.md),
+  [issue 129](../04-ISSUES/129-nothing-makes-a-machine-trust-the-meshs-authority/00-report.md)

02-DECISIONS/0139-a-network-is-forwarded-because-a-module-declared-it.md

@@ -0,0 +1,137 @@
+---
+topic: what runs on it
+status: superseded
+date: 2026-09-28
+deciders: jochen
+reconstructed: false
+extends: 02-DECISIONS/0137-a-machine-says-which-networks-it-routes.md
+superseded-by: 02-DECISIONS/0140-the-filter-constrains-what-arrives-from-outside.md
+---
+
+# 139. A network is forwarded because a module declared it
+
+## Context
+
+[ADR 0137](0137-a-machine-says-which-networks-it-routes.md), decided the same week, gave a machine a
+way to say which networks it routes for its guests. It was written because the derived filter's
+forward chain allowed two ranges named as constants in the control plane's source — the container
+runtime's bridge pool, and part of the pool its compose files are given — with a comment admitting
+the gap: *a machine whose runtime is configured with something else needs this to say so, which is a
+thing the mesh cannot derive.*
+
+**It can be derived, and from the right place.** Measured on the last machine still to be converged
+([issue 141](../04-ISSUES/141-the-forward-chain-does-not-follow-the-modules/00-report.md)): twenty-one
+container networks, nine inside the runtime's bridge pool, twelve in the other private range, and six
+of those outside the constant's lower bound — so the flip would have cut their guests off exactly as
+it did on the workstation that produced 0137.
+
+Naming a range to cover the six is what 0137 provides for, and it is the wrong instrument. Of those
+six networks, **four are networks the mesh's own modules declare**, present as network resources in
+the node's plan and created by the host because a module asked for them. **Two are the predecessor's
+leftovers** — compose networks of services the mesh does not run. Any range wide enough to keep the
+four forwards the two as well: a firewall widened by hand to protect networks that should not exist.
+
+The mesh already knows which of the twenty-one are its own, because it made them.
+
+**And the node's configuration is meant to follow the modules assigned to it.** That is the mesh's
+founding shape — the machine runs modules, and its files, its filter and its accounts are composed
+from what runs there ([ADR 0005](0005-the-node-host.md),
+[ADR 0010](0010-delivery.md),
+[ADR 0045](0045-a-machine-firewall-is-the-sum-of-what-it-listens-on.md)). The forward chain is the
+one derived thing that consults a constant and a list a person types.
+
+## Considered Options
+
+1. **Keep 0137 as it stands** — two constants plus a named list. Rejected: the list is written in
+   addresses, and addresses are what the runtime allocates, so the only entry safe enough to keep a
+   machine working is wider than the truth. It cannot distinguish a network the mesh made from one
+   left behind, which is the distinction that decides whether forwarding it is correct.
+2. **Derive it from what the machine reports.** Still rejected, on 0137's own grounds: a test bed
+   creates its bridge between one declaration and the next, and a filter that follows whatever
+   appeared on a machine is a firewall that widens itself. **This decision is not that** — see below.
+3. **Have the control plane allocate each module network's range from a pool it owns,** so it can
+   render the address itself. Rejected: more machinery for no gain. The runtime already allocates and
+   the host already knows, and taking allocation over means the mesh owning an address space it has no
+   other reason to own.
+4. **Have each module declare its network's range.** Rejected by
+   [ADR 0112](0112-a-module-definition-names-no-node-mesh-or-path.md): a definition names no address,
+   and the same definition runs on machines whose runtimes have allocated differently.
+
+## Decision
+
+**A network is forwarded because a module declared it.** Per node, the forward chain forwards the
+networks of the modules assigned there, and by default nothing else. A module unassigned stops being
+forwarded at the next reconcile.
+
+**The host resolves a declared network to its addresses.** A network resource carries a name; the
+runtime allocates the subnet when the network is created. So the control plane declares *forward the
+networks these modules asked for* and the host — which made them, and already resolves a container by
+its name — renders the addresses. [ADR 0005](0005-the-node-host.md) holds: the host applies, it does
+not decide.
+
+**Deriving from the declaration is not deriving from the machine.** Both of 0137's objections fall
+away. The set is known before the network exists, because a module declared it, so a network created
+between two declarations is already in the one that asked for it. And it cannot widen itself: a
+network nobody declared is never forwarded, however it appeared on the machine.
+
+**The runtime's own default bridge is forwarded, from what the runtime reports.** Containers that name
+no module network attach to it, and it belongs to the runtime rather than to any module — so the host
+renders it from what the runtime says, not from a range named in the control plane. The constants go.
+
+**What a machine says is for guests no module declares.** A test bed is not a module and its range is
+not a module's; that is the case 0137's mechanism is for, and it keeps it — added to the derived set,
+never replacing it, as 0137 decided. Narrowed to that, it is named for it.
+
+**Their guests keep address and name service**, per declared network, unchanged from
+[ADR 0137](0137-a-machine-says-which-networks-it-routes.md): the input chain admits that network's own
+DHCP and DNS and nothing else.
+
+## Consequences
+
+- **The two constants are removed**, and with them the class of fault that a machine's guests depend
+  on a range that describes some other machine.
+- **This is a behaviour change, not a refactor.** On the machine measured, the derived set and the
+  constant do not cover the same ground — that is the whole reason for the record. A machine whose
+  module networks happen to fall inside the old ranges renders the same rules.
+- **A range that exists only to keep a leftover alive becomes visible as such**, because it will not
+  be in the derived set and has to be said out loud to survive.
+- **`node networks` narrows** to guests no module declares, and the preview says which of a machine's
+  networks are the mesh's and which are not, so the difference is readable before a flip rather than
+  after.
+- **A module's declaration gains nothing.** It already declares its network; what changes is that the
+  filter reads it.
+- **What got harder:** the host renders part of the forward chain from what it created, so the
+  control plane no longer holds the whole rule set as text. The rule the mesh states is the set of
+  networks; the addresses are the machine's.
+
+## How it is checked
+
+- **Only declared networks are forwarded.** A node with two modules that declare networks renders
+  forward rules for exactly those two, and none for a third network present on the machine that no
+  module declared. This fails against the previous behaviour, which forwards by range and cannot tell
+  them apart, and that is how it is written.
+- **Unassigning a module removes its network's rule** at the next reconcile, asserted on the rendered
+  chain rather than on the intent.
+- **Guests of a declared network keep address and name service**, asserted per chain body so a line in
+  the wrong chain cannot pass — carried from 0137.
+- **The runtime's own default bridge comes from the runtime**, asserted by rendering for a runtime
+  whose default bridge is somewhere other than the range the constant named.
+- **A machine that names a range for guests no module declares still gets it**, added to the derived
+  set and not replacing it.
+- **Each family is matched in its own syntax**, carried from 0137: one set holding both is a syntax
+  error, and a ruleset that does not load is a machine filtering nothing while its unit reports a
+  fault.
+
+## References
+
+- [ADR 0137](0137-a-machine-says-which-networks-it-routes.md) — narrowed here; its mechanism keeps the
+  case it is right for
+- [ADR 0005](0005-the-node-host.md) — the host applies; the addresses are the machine's
+- [ADR 0045](0045-a-machine-firewall-is-the-sum-of-what-it-listens-on.md) — the filter is derived from
+  what runs there
+- [ADR 0112](0112-a-module-definition-names-no-node-mesh-or-path.md) — why a module does not name its
+  range
+- [issue 141](../04-ISSUES/141-the-forward-chain-does-not-follow-the-modules/00-report.md) — the
+  measurement
+- [issue 137](../04-ISSUES/137-converging-a-machine-cut-off-its-own-guests/00-report.md) — the
+  breakage that produced 0137

02-DECISIONS/0140-the-filter-constrains-what-arrives-from-outside.md

@@ -0,0 +1,146 @@
+---
+topic: what runs on it
+status: accepted
+date: 2026-09-28
+deciders: jochen
+reconstructed: false
+extends: 02-DECISIONS/0045-a-machine-firewall-is-the-sum-of-what-it-listens-on.md
+supersedes:
+  - 02-DECISIONS/0137-a-machine-says-which-networks-it-routes.md
+  - 02-DECISIONS/0139-a-network-is-forwarded-because-a-module-declared-it.md
+---
+
+# 140. The filter constrains what arrives from outside, and says nothing about a machine's own guests
+
+## Context
+
+The filter the mesh derives blocks traffic passing *through* a machine unless something allows it,
+because a container's published port is traffic passing through rather than traffic arriving at the
+machine itself ([ADR 0100](0100-a-node-in-use-is-adopted-before-it-is-converged.md),
+[issue 047](../04-ISSUES/047-the-firewall-does-not-cover-published-container-ports/00-report.md)).
+Having blocked all of it, the filter then had to let the machine's own containers reach outward again.
+It does that by listing the address ranges those containers sit on.
+
+As rendered on a converged workstation today:
+
+```
+policy drop
+ct state established,related accept
+ip saddr 172.16.0.0/12 accept
+ip saddr 192.168.128.0/17 accept
+ip saddr 10.0.0.0/8 accept
+ip saddr 192.168.16.0/20 accept
+... four more
+```
+
+Two of those ranges were constants in the control plane's source. The rest were typed by the operator
+after [ADR 0137](0137-a-machine-says-which-networks-it-routes.md), which existed to make the typing
+possible, because converging that workstation had cut every one of its containers off from the
+internet and nothing reported a fault
+([issue 137](../04-ISSUES/137-converging-a-machine-cut-off-its-own-guests/00-report.md)).
+
+**The list is the mistake, not its contents.** Every attempt to make it correct fails the same way.
+A constant describes one machine. A typed range goes stale, and cannot tell a network the mesh made
+from one a predecessor left behind — measured on the control-node, where six such ranges fall outside
+the constants and two of the six belong to services the mesh does not run
+([issue 141](../04-ISSUES/141-the-forward-chain-does-not-follow-the-modules/00-report.md)).
+[ADR 0139](0139-a-network-is-forwarded-because-a-module-declared-it.md) tried to generate the same
+list from the modules and put half the rule set on the machine to do it. Three records, one list, and
+the list should not exist.
+
+**Because the mesh has no policy about a container reaching outward.** What the filter is for is
+stated in [ADR 0045](0045-a-machine-firewall-is-the-sum-of-what-it-listens-on.md): which port is open,
+and to whom. That is about what arrives. A container of this machine's own opening a connection to
+something else is not a port being opened to anybody, and enumerating the addresses it might do so
+from is bookkeeping about the machine's internal plumbing, which the mesh neither owns nor can know.
+
+**The system being replaced never had this fault, and its rule says why.** The chain still protecting
+the control-node applies only to traffic arriving on that machine's outward link, and leaves
+everything else alone. The mesh's filter dropped that distinction and replaced it with a list of
+addresses.
+
+## Considered Options
+
+1. **Keep the list and generate it better** — from the modules' declared networks, or from what the
+   machine reports. Rejected: [ADR 0139](0139-a-network-is-forwarded-because-a-module-declared-it.md)
+   is that, and it puts part of the rule set on the machine, which makes the rule set partly the
+   machine's and the derivation advisory.
+2. **Name the guest links instead of their addresses, and allow only those.** Rejected as more than is
+   needed: it fails in the safe direction, but it is still a list that has to keep up with the
+   machine, and the thing it protects against — a container reaching outward — is not a thing the mesh
+   has a position on.
+3. **Do not block traffic passing through at all.** Rejected: that is
+   [issue 047](../04-ISSUES/047-the-firewall-does-not-cover-published-container-ports/00-report.md),
+   where a published port was reachable from anywhere because no rule mentioned it.
+4. **Constrain what arrives from outside, and nothing else.** Adopted.
+
+## Decision
+
+**The filter constrains traffic arriving from outside the machine, and says nothing about traffic that
+did not.** Traffic passing through the machine is allowed unless it arrived on one of the machine's
+outward links, in which case it is allowed only where a declared endpoint's reach admits it
+([ADR 0138](0138-an-assignment-binds-an-endpoint-and-says-how-far-it-reaches.md)). A container of this
+machine's own reaching anywhere is not filtered, because the mesh has no position on it.
+
+**A machine says which of its links face outside.** One node-level fact, reported by the machine the
+way it already reports the kind of firewall it found and the tunnel it carries — not a setting, not a
+list of addresses, and not something anybody types. It does not change when a module is added or
+removed, which is what separates it from the list it replaces.
+
+**A machine that has reported no outward link is sent no filter.** Rendering a rule around a link
+whose name is not known produces a rule set that does not load, which is a machine filtering nothing
+while its unit reports success. The refusal happens in the control plane, where a person reads it, and
+the machine keeps the filter it already has.
+
+**No addresses of the machine's own networks appear in the filter.** The two constants are removed and
+`node networks` is removed with them, along with everything any machine was told to say through it.
+Ports continue to follow the modules exactly as before: a module assigned to a machine opens the port
+its assignment says it reaches on, and nothing about a network is said anywhere.
+
+## Consequences
+
+- **Three records collapse into one rule.** 0137 and 0139 are superseded. What 0137 was right about —
+  that converging a machine had silently cut off its own containers, and that nothing previewed it — is
+  answered by removing the cause rather than by giving the operator a way to compensate for it.
+- **Every machine already converged loses its declared ranges and keeps working**, because the traffic
+  those ranges allowed is now allowed by not having arrived from outside. The workstation's five ranges
+  and the laptop's one are deleted rather than migrated.
+- **A machine's test beds stop being a special case.** A bed's network is created while the machine
+  runs and was the case no list could cover; it is now covered by not being mentioned.
+- **A new fact travels in the report**, and the control plane refuses to compose a filter without it,
+  so the order of the roll-out matters: the machines report before the control plane depends on it.
+- **A machine with more than one outward link says so**, and a machine that acquires one while the mesh
+  is not looking is treated as internal until its next report. That window is the cost of this shape;
+  it is bounded by the report interval, and it exists on machines whose outward link changes, which
+  are the machines with nothing published to the outside.
+- **What got harder:** nothing in the declaration, and one more thing a machine must be able to work
+  out about itself. A machine that cannot say which link faces outside cannot be given a filter.
+
+## How it is checked
+
+- **A machine's own container reaches outward with no network named anywhere.** A bed converges a
+  machine carrying containers on several networks, none of them mentioned in any setting, and each
+  reaches out afterwards. This fails against the previous behaviour, where the same flip cut them off,
+  and that is how it is written.
+- **A port declared reachable from outside is reachable; one that is not, is not.** Probed from off the
+  machine's private network, for a published port and for an undeclared one, before and after the flip.
+- **A network created after the filter was composed needs no new filter.** A network is made on the
+  machine after its last declaration and a container on it reaches out, with nothing re-sent.
+- **No address of a machine's own networks appears in a rendered filter**, asserted on the text so a
+  range cannot creep back in.
+- **A machine that reports no outward link is sent no filter, and the refusal names it** — asserted in
+  the control plane, and that the machine's existing filter is left alone.
+- **A machine reporting two outward links has both constrained**, asserted per chain body so a rule
+  covering one and not the other cannot pass.
+
+## References
+
+- [ADR 0045](0045-a-machine-firewall-is-the-sum-of-what-it-listens-on.md) — what the filter is for
+- [ADR 0138](0138-an-assignment-binds-an-endpoint-and-says-how-far-it-reaches.md) — what admits traffic
+  arriving from outside
+- [ADR 0100](0100-a-node-in-use-is-adopted-before-it-is-converged.md) — why traffic passing through is
+  filtered at all
+- [ADR 0137](0137-a-machine-says-which-networks-it-routes.md),
+  [ADR 0139](0139-a-network-is-forwarded-because-a-module-declared-it.md) — superseded here
+- [issue 137](../04-ISSUES/137-converging-a-machine-cut-off-its-own-guests/00-report.md),
+  [issue 141](../04-ISSUES/141-the-forward-chain-does-not-follow-the-modules/00-report.md)

02-DECISIONS/0141-the-host-delivers-its-own-successor.md

@@ -0,0 +1,154 @@
+---
+topic: what runs on it
+status: accepted
+date: 2026-09-29
+deciders: jochen
+reconstructed: false
+extends: 02-DECISIONS/0005-the-node-host.md
+---
+
+# 141. The host delivers its own successor, and versions live side by side
+
+## Context
+
+[Issue 142](../04-ISSUES/142-the-host-is-the-one-thing-the-mesh-does-not-deliver/00-report.md). A
+merge builds every changed module and the control plane — which is itself a module — and the result
+reaches the machines running it with nobody asking. The host is the exception: it is not a build
+target, no declaration delivers it, and every machine in this mesh runs a byte-identical binary that
+somebody built on a workstation and copied out.
+
+The half that *recovers* from a bad host exists. `internal/upgrade` can tell that the executable this
+process started from was replaced on disk, and it records which version last completed a reconcile.
+The launcher counts consecutive failed starts, calls a rollback at the limit, and treats a clean exit
+as the host standing aside so that the next loop runs whatever is on disk now. That supervision is
+complete and correct.
+
+Two things make it dead code:
+
+- **`Replaced()` is called by nothing but its own tests.** Nothing tells the running host that a
+  successor is waiting.
+- **The rollback resolves a version through the machine's package manager** — `pacman -U` from the
+  package cache. No machine here has the host installed as a package, so the recovery cannot run on
+  any of them; and being written in one package manager's terms, it cannot run on two of the three
+  operating systems the host is built for — [ADR 0005](0005-the-node-host.md) builds one binary per
+  operating system, pinned at link time.
+
+**The record already points at the answer.** What is kept is a *version*, not a path. Keeping a
+version is only useful to something that can choose between versions present on the machine, which is
+what the package manager was being asked to do. The versions can simply be on disk.
+
+## Considered Options
+
+1. **Deliver the host as a package, as the rollback assumes.** Rejected: it needs a package built and
+   a repository trusted per operating system, three of each, and the existing `package` resource
+   asserts presence and deliberately never a version — "version is the package manager's business and
+   the mesh does not hold a second opinion about it" — so it cannot ask for a particular host anyway.
+   Heaviest of the three and the only one that is different on every machine.
+2. **Write the new binary over the running one.** Rejected on a fact: a running executable cannot be
+   truncated, and `archive` opens what it unpacks with `O_TRUNC`. It could be made to write and
+   rename, which is better hygiene and worth doing for its own sake, but it buys nothing here that
+   option 3 does not, and it leaves rollback with nowhere to go back to.
+3. **Versions side by side; the newest retires the old.** Adopted.
+
+## Decision
+
+**A host version is delivered as an archive into a directory named for it, and never over a running
+one.** The declaration names it like any other archive — fetched by digest, the digest checked before
+anything is unpacked. Nothing new travels, no new resource kind, and no change to how archives are
+applied, because the path being written is not the path being executed.
+
+**The launcher starts the most recently delivered version.** That is what "the newest" means: the
+version whose directory arrived last. It reads no pointer and follows no link — the mesh creates no
+links ([ADR 0012](0012-the-mesh-creates-no-symlinks.md)) — and the version is in the path, so nothing
+has to be told what is running.
+
+**The running host stands aside for a successor, and only between reconciles.** Finding a newer
+version delivered, it finishes the reconcile it is in and exits cleanly. The launcher already reads a
+clean exit as exactly this and starts what is on disk now. A host that stood aside mid-apply is the
+half-configured machine this project exists to prevent, so the check happens at the boundary and
+nowhere else.
+
+**A version that completes a reconcile records itself, and retires what came before it.** The
+known-good record is written as it is today. Then versions older than the one before the running one
+are removed: the running version and its predecessor are kept, which is exactly what a rollback
+needs, and nothing else accumulates.
+
+**Rollback starts the previous version instead of reinstalling a package.** At the failure limit the
+launcher pins the known-good version and starts that, once. The second failure is still a different
+diagnosis — the previously working version does not run either, so it is the machine and not the
+binary — and the halt is unchanged. No package manager, no package cache, and the same script on every
+operating system.
+
+**A machine says which host version it is running,** on the report it already sends, beside the other
+facts it states about itself. Without it nothing can say a machine is behind, so "every machine
+current with its source" cannot include the host.
+
+## Progressive insight — 2026-09-29, the same day
+
+**The delivery is not "nothing new", and this record said it was.** The decision above stands and is
+built: versions side by side, the newest runs, the running host stands aside between reconciles, a
+completed reconcile retires what is older than the predecessor, rollback picks a directory. What was
+wrong was a claim about how a version reaches a machine. The paragraph on delivery said the
+declaration "names it like any other archive… nothing new travels, no new resource kind"; the second
+half is true and the first is not, because two things the delivery needs do not exist:
+
+- **Nothing can compile it.** A `bundle` artifact is compiled by a closed list of toolchains —
+  typescript and python — whose own comment says adding a language is a decision, because a language
+  used by *modules* needs an SDK carrying the broker client, the event envelope and tool serving. The
+  host uses none of that: it is what applies modules, not one of them. So the obligation that list
+  warns about attaches to a module written in a language, not to the language being buildable, and
+  the control plane — also written in Go — is built as an image from a Dockerfile rather than through
+  a toolchain at all.
+- **A version cannot reach the path.** An `archive` resource names a fixed path in the manifest, and
+  nothing interpolates the built version into it, so nothing can ask for
+  `…/versions/<version>/`.
+
+Neither changes what was decided, which options were weighed, or any consequence: the shape is
+unaffected and the host half is merged and tested. What it changes is the cost, which this record
+understated as none. The remaining work is a way to build the host and a way to name a version in a
+path, and until both exist nothing delivers a version and every machine takes the fallback — which is
+what every machine does today.
+
+## Consequences
+
+- **The host becomes a build target and a module** — a module whose resource is the next host, applied
+  by the host that is running. The bootstrap is not circular because the two are different versions in
+  different directories.
+- **Rollback becomes usable on every machine**, having been usable on none. It also stops being
+  written in one operating system's terms.
+- **One copy by hand remains, once.** The first host that understands versioned directories cannot be
+  fetched by a host that does not. That copy is the last, and it is the honest cost of the change
+  rather than a step in the design.
+- **Two versions occupy disk instead of one.** About nine megabytes. The predecessor is the price of a
+  rollback that does not depend on a cache somebody else may clean.
+- **What got harder:** a host must now be able to find its own successor and to judge when it is safe
+  to stand aside. Both are between reconciles, which is the only moment the host is not mid-change.
+- **A machine that is never told a newer version keeps running what it has**, indefinitely and
+  visibly, because its report says which version that is.
+
+## How it is checked
+
+- **A delivered version is run, and the old one is not.** A bed delivers a second version to a machine
+  running the first; the host exits between reconciles, the launcher starts the new one, and the
+  machine reports the new version. This fails against the previous behaviour, where nothing notices a
+  delivered version at all.
+- **It stands aside between reconciles and never inside one.** Asserted by delivering a version while
+  an apply is in flight: the apply completes, and the exit follows it.
+- **A version that will not start is rolled back to its predecessor, once**, and the second failure
+  halts with the machine named rather than the binary — asserted with no package manager involved.
+- **A completed reconcile retires what is older than the predecessor**, and never the predecessor
+  itself, because that is what a rollback needs. Asserted on the directory afterwards.
+- **The report names the running version**, asserted end to end rather than on the function that reads
+  it, since the point is that the control plane can tell a machine is behind.
+- **The launcher picks the newest delivered version** with no pointer file and no link, asserted by
+  delivering two and checking which runs.
+
+## References
+
+- [ADR 0005](0005-the-node-host.md) — the host, and what its supervision is for
+- [ADR 0010](0010-delivery.md) — a declaration is owned resources; this adds no kind to it
+- [ADR 0012](0012-the-mesh-creates-no-symlinks.md) — why the version is in the path
+- [ADR 0005](0005-the-node-host.md), *it is built per operating system* — why a rollback written in
+  one package manager's terms was wrong for two of three
+- [issue 142](../04-ISSUES/142-the-host-is-the-one-thing-the-mesh-does-not-deliver/00-report.md) — the
+  measurement

02-DECISIONS/0142-the-mesh-delivers-its-own-components-as-binaries.md

@@ -0,0 +1,158 @@
+---
+topic: the mesh
+status: accepted
+date: 2026-09-29
+deciders: jochen
+reconstructed: false
+extends: 02-DECISIONS/0141-the-host-delivers-its-own-successor.md
+---
+
+# 142. The mesh delivers its own components as binaries, not as container images
+
+## Context
+
+Measured on the control-node, 2026-09-29:
+
+| what | how it runs | publishes |
+|---|---|---|
+| host | a binary on the machine | — |
+| controller, catalogue, builder, vault | containers | nothing |
+| store, registry, broker | containers | ports |
+
+**The mesh's own software is delivered two ways, and the difference is not a property of the
+software.** The host and the controller are both written in the same language, both the mesh's own,
+both doing the mesh's own work. One is an image fetched from a registry. The other is a file somebody
+copied to four machines, owned by no package, built by nothing
+([issue 142](../04-ISSUES/142-the-host-is-the-one-thing-the-mesh-does-not-deliver/00-report.md)).
+
+**The reason is not a judgement about either, it is that images are the only delivery that works.**
+There is no way to put a binary on a machine. The host is hand-copied because of that, and the
+controller is an image because of that. Neither was chosen on its merits.
+
+What it costs, all of it measured rather than argued:
+
+- **Genesis must raise a container runtime before the control plane can exist.** The bundle carries
+  three images and one of them is the controller, *"in the bundle for the same reason they are: there
+  is nothing to fetch it with yet"*
+  ([design 07](../03-DESIGN/01-to-be/07-the-foundation.md)). So the hardest moment in the mesh's life
+  has a prerequisite that the thing being started does not need.
+- **Updating the control plane depends on the control plane.** Its image is fetched from the registry,
+  which is a container the controller manages.
+- **A change to the host cannot be rolled out at all.** Every machine here runs a byte-identical
+  hand-copied binary. A change merged yesterday reached none of them.
+- **Compiling the language the mesh is written in is not a capability of the builder.** The bundle
+  toolchains are typescript — real, with a registered base module — and python, which is named in the
+  list and absent from the catalogue. The controller is built as an image from a Dockerfile, which is
+  the per-repository incantation the bundle toolchain exists to abolish
+  ([design 18](../03-DESIGN/01-to-be/18-building-a-module.md)).
+
+The half that *receives* a binary safely is already built and tested
+([ADR 0141](0141-the-host-delivers-its-own-successor.md)): versions side by side in directories named
+for them, the newest run, the running one standing aside between reconciles, retirement keeping the
+predecessor, and a rollback that chooses a directory. What is missing is everything that puts one
+there.
+
+## Considered Options
+
+1. **Leave it as it is.** Rejected: it is not a design, it is the reach of one mechanism. And it is
+   what makes a host change undeliverable.
+2. **Containerise the host too**, so everything is delivered one way. Rejected: the host is what
+   starts the container runtime and what applies containers. A host in a container is the bootstrap
+   problem made total, and the machine would have no way back from a bad one.
+3. **Deliver the mesh's components as operating-system packages.** Rejected for the reason
+   [ADR 0141](0141-the-host-delivers-its-own-successor.md) rejected it for the host: a package and a
+   trusted repository per operating system, three of each, and the `package` resource asserts presence
+   and deliberately never a version.
+4. **Binaries for the mesh's own components, containers for third-party software.** Adopted.
+
+## Decision
+
+**The mesh's own components are delivered as binaries on the machine.** The host, the controller, the
+catalogue, the builder, the vault — the software this project writes. They are delivered by the
+mechanism [ADR 0141](0141-the-host-delivers-its-own-successor.md) built: an archive, fetched by
+digest, unpacked into a directory named for its version, with the running one standing aside between
+reconciles and a rollback that chooses the predecessor.
+
+**Third-party software stays a container.** The store, the registry, the broker. They are somebody
+else's build, they are already adopted as modules
+([ADR 0078](0078-the-store-and-broker-are-modules.md)), and an image is the right way to carry
+somebody else's software. **The container runtime remains required** — modules use it — so this
+removes a dependency from the control plane, not from the machine.
+
+**The builder compiles the languages the mesh is written in.** A toolchain for Go, with a base module
+providing the compiler, exactly as typescript has. The obligation the toolchain list warns about — an
+SDK carrying the broker client, the envelope and tool serving — attaches to a *module* written in a
+language, not to the language being compilable. None of these components is a module in that sense;
+the host is what applies modules.
+
+**An artifact says what it targets.** A compiled binary is per operating system, pinned at link time
+([ADR 0005](0005-the-node-host.md)), and a toolchain deliberately takes nothing from the module,
+because anything a module could override there it would be writing a Dockerfile to override. So the
+target is a property of the artifact rather than of the recipe, and one artifact declared per target
+is one build each.
+
+**A component's version comes from where it sits, not from its linker.** It is unpacked into a
+directory named for its version, so it can read its own version from its path. The stamp goes, and
+with it the need for a build to know what it will be called.
+
+**Genesis carries a binary reference where it carried an image reference.** The principle does not
+change — the bundle names a thing by digest and the host fetches it, pinned because nothing can
+resolve a version when no mesh exists — and the container runtime stops being a prerequisite for the
+control plane. It stays a prerequisite for the store and the broker, which is where it belongs.
+
+**The order is staged, and each step stands alone.** Compiling Go; an artifact naming its target;
+delivering a binary; the host as the first component delivered; the controller, catalogue, builder and
+vault out of their containers; genesis last. Genesis is last for the reason it is always last: it
+matters for a machine nobody has yet, and every earlier step is provable on a mesh that exists.
+
+## Consequences
+
+- **One delivery for the mesh's own software**, so a change to the host ships the way a change to the
+  controller does, and neither is copied by hand.
+- **The control plane stops depending on a container runtime and on its own registry.** Both remain on
+  the machine for other reasons; neither gates the control plane's own life any more.
+- **`Replaced()`, the known-good record and the launcher's rollback stop being dead code.** They were
+  written for this and have been called by nothing but their tests.
+- **Four more components gain a rollback they do not have.** Today a bad controller image is recovered
+  by an operator; under this it is recovered the way a bad host is.
+- **Two versions of each component occupy disk.** Around nine megabytes each. The predecessor is what a
+  rollback needs.
+- **Genesis gets smaller, not larger.** One fewer image to carry and one fewer runtime to raise before
+  the control plane.
+- **This does not make the components smaller or simpler.** They are the same programs; what changes is
+  how they arrive. A reader expecting the containers to have been hiding complexity will not find any.
+- **What got harder:** the builder gains a language, artifacts gain a target, and the mesh gains a
+  second kind of thing it must deliver correctly — one where getting it wrong takes the control plane
+  down rather than a module. That is why the host is first: it is the component whose recovery is
+  already built and tested.
+
+## How it is checked
+
+- **A component is delivered and runs, with nothing copied by hand.** A bed builds the host from its
+  repository, delivers it to a machine running an older one, and the machine reports the new version.
+  This fails today at the first step, because nothing builds it.
+- **Each target is built once and only the matching one is delivered.** Asserted by declaring an
+  artifact per operating system and checking that a machine is offered the one it can run — a host
+  built for another is what ADR 0005's link-time pin exists to refuse.
+- **A component reads its version from its path**, asserted by unpacking the same bytes into two
+  differently named directories and seeing each report its own.
+- **A bad component is rolled back without an operator**, for the host first: a version that will not
+  start is replaced by its predecessor once, and the second failure halts naming the machine.
+- **The control plane comes up with no registry reachable**, which is the dependency this removes —
+  asserted by raising it with the registry stopped.
+- **Genesis raises a control plane with no container runtime running**, and raises the store and the
+  broker afterwards. Last, and on a machine with nothing on it.
+- **A published port count that does not change.** The mesh's own components publish nothing today, so
+  moving them out of containers must not open anything — asserted on the machine's reachable set before
+  and after, which the converge preview already reads.
+
+## References
+
+- [ADR 0141](0141-the-host-delivers-its-own-successor.md) — the receiving half, already built
+- [ADR 0005](0005-the-node-host.md) — the host, its supervision, and one binary per operating system
+- [ADR 0078](0078-the-store-and-broker-are-modules.md) — why third-party software stays a container
+- [ADR 0006](0006-the-substrate-and-the-control-plane.md) — what genesis must raise, and in what order
+- [issue 142](../04-ISSUES/142-the-host-is-the-one-thing-the-mesh-does-not-deliver/00-report.md) — the
+  measurement that started this
+- [design 07](../03-DESIGN/01-to-be/07-the-foundation.md) — the bundle's three images, one of them the
+  controller

02-DECISIONS/README.md

@@ -134,6 +134,15 @@ python3 00-META/checks/index.py            fail if stale
 - **0106** — [The bus is NATS](0106-the-bus-is-nats.md)
 - **0116** — [The bus is built in five steps, and the protocol moves with it](0116-the-bus-is-built-in-five-steps.md)
 - **0119** — [A taken tunnel's predecessor is retired once the take is proven](0119-a-taken-tunnels-predecessor-is-retired.md)
+- **0125** — [The bus is the only broker](0125-the-bus-is-the-only-broker.md)  *(superseded)*
+- **0127** — [AMQP is a provision, not the bus](0127-amqp-is-a-provision-not-the-bus.md)  *(superseded)*
+- **0128** — [The mesh bus is required, not ambient](0128-the-mesh-bus-is-required-not-ambient.md)
+- **0129** — [A seat carries the protocol of its role](0129-a-seat-carries-the-protocol-of-its-role.md)
+- **0130** — [The predecessor is ending, and its broker goes with it](0130-the-predecessor-is-ending-and-its-broker-goes-with-it.md)
+- **0131** — [Everything on the mesh speaks to the broker seat, and AMQP is not a provision](0131-everything-on-the-mesh-speaks-to-the-broker-seat.md)
+- **0132** — [A seat carries the tools its holder must serve](0132-a-seat-carries-the-tools-its-holder-must-serve.md)
+- **0134** — [The mesh says what it applied](0134-the-mesh-says-what-it-applied.md)
+- **0142** — [The mesh delivers its own components as binaries, not as container images](0142-the-mesh-delivers-its-own-components-as-binaries.md)
 
 ### Its tiers, from the bottom up
 
@@ -164,6 +173,7 @@ python3 00-META/checks/index.py            fail if stale
 - **0098** — [A fact a provider makes at first start is fetched from it, not carried in its manifest](0098-a-fact-a-provider-makes-at-first-start-is-fetched-from-it.md)
 - **0108** — [A route carries the policy applied to a request, and names a secret rather than holding one](0108-a-route-carries-the-policy-applied-to-a-request.md)
 - **0109** — [A package registry seat is one per ecosystem, not one for all of them](0109-a-package-registry-seat-is-one-per-ecosystem.md)
+- **0126** — [A module declares its own seats; the mesh reserves its own](0126-a-module-declares-its-own-seats.md)
 
 ### What runs on them, and how it gets there
 
@@ -196,12 +206,23 @@ python3 00-META/checks/index.py            fail if stale
 - **0091** — [A mount is declared, and there are three things it can be](0091-a-mount-is-declared-three-ways.md)
 - **0099** — [A step that runs once names what it reads, and runs again when it changed](0099-a-step-that-runs-once-names-what-it-reads.md)
 - **0110** — [A seat is held by one assignment, from a closed set, and it may deliver a provision](0110-a-seat-is-a-module-assignment-from-a-closed-set.md)
-- **0112** — [A module definition names no node, no mesh and no path: everything it needs is a requirement the mesh resolves](0112-a-module-definition-names-no-node-mesh-or-path.md)  *(proposed)*
+- **0112** — [A module definition names no node, no mesh and no path: everything it needs is a requirement the mesh resolves](0112-a-module-definition-names-no-node-mesh-or-path.md)
 - **0113** — [The vault makes every shared secret, a provider makes resources and data, and the mesh carries both](0113-the-vault-makes-every-secret.md)  *(proposed)*
 - **0114** — [A credential two parties hold rotates over two credentials; one a single party holds rotates in place, staged; and retiring a credential never removes what it reached](0114-a-shared-credential-rotates-over-two-credentials.md)  *(proposed)*
 - **0115** — [One assignment of a module per node: the module's name is the assignment's identity](0115-one-assignment-of-a-module-per-node.md)  *(proposed)*
 - **0117** — [A machine's uplink is a seat: the mesh configures the manager, never the link](0117-a-machines-uplink-is-a-seat.md)
 - **0118** — [Undeclaring removes what the mesh made, and gives a unit back the state it was found in](0118-undeclaring-gives-a-unit-back-the-state-it-was-found-in.md)
+- **0120** — [A roster fact carries its format as a template: the mesh owns the data, the module owns the format](0120-a-roster-fact-carries-its-format-as-a-template.md)
+- **0121** — [A system seat is named for its scope, and a module may define its own](0121-a-system-seat-is-named-for-its-scope-and-modules-define-their-own.md)
+- **0122** — [A seat is data the controller owns, and a rename is a database update](0122-a-seat-is-data-a-rename-is-a-database-update.md)
+- **0133** — [A module owns its migrations, and the mesh owns when they run](0133-a-module-owns-its-migrations-and-the-mesh-owns-when-they-run.md)  *(superseded)*
+- **0135** — [A module version prepares its state before it runs](0135-a-module-version-prepares-its-state-before-it-runs.md)
+- **0136** — [A step gates its module, not the machine](0136-a-step-gates-its-module-not-the-machine.md)
+- **0137** — [A machine says which networks it routes](0137-a-machine-says-which-networks-it-routes.md)  *(superseded)*
+- **0138** — [An assignment binds an endpoint and says how far it reaches](0138-an-assignment-binds-an-endpoint-and-says-how-far-it-reaches.md)
+- **0139** — [A network is forwarded because a module declared it](0139-a-network-is-forwarded-because-a-module-declared-it.md)  *(superseded)*
+- **0140** — [The filter constrains what arrives from outside, and says nothing about a machine's own guests](0140-the-filter-constrains-what-arrives-from-outside.md)
+- **0141** — [The host delivers its own successor, and versions live side by side](0141-the-host-delivers-its-own-successor.md)
 
 ### How it is built
 

03-DESIGN/01-to-be/05-the-node-host.md

@@ -2,8 +2,9 @@
 layer: to-be
 status: in-progress
 code: [mesh-host]
-updated: 2026-09-22
+updated: 2026-09-29
 decisions:
+  - 02-DECISIONS/0141-the-host-delivers-its-own-successor.md
   - 02-DECISIONS/0100-a-node-in-use-is-adopted-before-it-is-converged.md
   - 02-DECISIONS/0102-the-mesh-writes-into-a-shared-file-never-over-it.md
   - 02-DECISIONS/0103-what-an-adopted-node-holds-and-what-its-guard-refuses.md
@@ -423,3 +424,45 @@ ignored an instruction and "applied" would be a lie. Applying stays one at a tim
 is not. **Checked** by the link's unit tests on the drain, and by the genesis bed's settle wait,
 which counts on a node catching up to the newest declaration rather than the oldest.
 
+## The host delivers its own successor
+
+*2026-09-29, from a change to the host that could reach no machine —
+[issue 142](../../04-ISSUES/142-the-host-is-the-one-thing-the-mesh-does-not-deliver/00-report.md),
+settled by [ADR 0141](../../02-DECISIONS/0141-the-host-delivers-its-own-successor.md).*
+
+A merge builds every changed module and the control plane, and the result reaches the machines running
+it with nobody asking. The host was the exception: not a build target, named by no declaration, and
+identical on every machine because somebody had copied it there.
+
+The supervision needed for this was already right. A clean exit from the host means it has stood aside,
+and the launcher's next turn runs whatever is on disk. Consecutive failed starts are counted, a
+rollback happens at the limit, and a second failure halts with the machine named rather than the binary.
+What was missing was smaller than it looked: nothing told the running host a successor was waiting, and
+the rollback resolved its known-good *version* through one operating system's package manager, which no
+machine here used.
+
+Keeping a version rather than a path was the clue. That is only useful to something that can choose
+between versions present on the machine — so the versions live side by side:
+
+- **A version arrives as an archive, in a directory named for it.** The ordinary resource, fetched by
+  digest and checked before anything is unpacked. The path written is never the path being executed, so
+  replacing a running binary — which the kernel refuses — never comes up.
+- **The launcher starts the most recently delivered version**, reading no pointer and following no
+  link, because the version is in the path.
+- **The running host stands aside between reconciles and never inside one.** Standing aside mid-apply is
+  the half-configured machine this document exists to prevent.
+- **A version that completes a reconcile records itself and retires what is older than its
+  predecessor.** The predecessor stays, because that is what a rollback needs.
+- **Rollback starts that predecessor** instead of reinstalling a package: no package manager, no cache
+  somebody else may clean, and the same script on every operating system.
+- **A machine says which host version it runs**, on the report it already sends, so being behind is
+  answerable at all.
+
+One copy by hand remains, once: the first host that understands versioned directories cannot be fetched
+by a host that does not.
+
+*How it is checked* is stated with the decision — a second version delivered to a running machine is
+run and reported; the exit follows an in-flight apply rather than interrupting it; a version that will
+not start is rolled back once and the second failure halts; a completed reconcile retires what is older
+than the predecessor and never the predecessor; and the newest of two delivered versions is the one
+that runs.

03-DESIGN/01-to-be/07-the-foundation.md

@@ -11,8 +11,9 @@ code:
   - mesh-catalog modules/postgres
   - mesh-catalog modules/lavinmq
   - mesh-lab test/integration/mesh.test.ts (a bare machine becomes a mesh)
-updated: 2026-09-22
+updated: 2026-09-29
 decisions:
+  - 02-DECISIONS/0142-the-mesh-delivers-its-own-components-as-binaries.md
   - 02-DECISIONS/0100-a-node-in-use-is-adopted-before-it-is-converged.md
   - 02-DECISIONS/0088-the-foundation-filters-before-anything-listens.md
   - 02-DECISIONS/0004-a-node-and-how-it-joins.md
@@ -314,4 +315,24 @@ of a database and pushed to over the broker. What arrived and what did not is th
 
 **One fault, and it was in the joining.** The token did not say what the mesh calls the machine,
 so enrolment needed a flag its own help said it did not — and failed at the broker with an empty
-username. Recorded in ADR 0004 as the fifth thing a token carries.
+username. Recorded in ADR 0004 as the fifth thing a token carries.
+
+## The mesh's own components arrive as binaries
+
+*2026-09-29 —
+[ADR 0142](../../02-DECISIONS/0142-the-mesh-delivers-its-own-components-as-binaries.md).*
+
+The bundle carries three images and one of them is the controller, *because there is nothing to fetch
+it with yet*. That reasoning holds and its conclusion changes: the controller is carried as a **binary**
+reference rather than an image reference, pinned by digest exactly as before. Nothing about the bundle's
+shape moves — it names a thing and the host fetches it — and the container runtime stops being something
+genesis must raise before the control plane can exist. It still raises one, for the store and the broker,
+which is where somebody else's software belongs.
+
+The mesh's own components — the host, the controller, the catalogue, the builder, the vault — are
+delivered as binaries into directories named for their versions, by the mechanism
+[ADR 0141](../../02-DECISIONS/0141-the-host-delivers-its-own-successor.md) describes. Third-party
+software stays a container. The split is not about isolation; it is about who built the thing.
+
+Measured before deciding it: the mesh's own components publish no ports at all, so this opens nothing.
+Only the store, the registry and the broker publish, and they are staying as they are.

03-DESIGN/01-to-be/08-connectivity.md

@@ -7,8 +7,10 @@ code:
   - mesh-controller internal/identity/authority.go
   - mesh-host internal/identity/serving.go
   - mesh-host internal/apply (the service that reflects a rule set)
-updated: 2026-09-27
+updated: 2026-09-28
 decisions:
+  - 02-DECISIONS/0138-an-assignment-binds-an-endpoint-and-says-how-far-it-reaches.md
+  - 02-DECISIONS/0140-the-filter-constrains-what-arrives-from-outside.md
   - 02-DECISIONS/0104-a-provision-may-be-answered-by-an-adapter-to-the-predecessor.md
   - 02-DECISIONS/0106-the-bus-is-nats.md
   - 02-DECISIONS/0105-the-mesh-adopts-the-predecessors-tunnel-in-place.md
@@ -625,6 +627,50 @@ the found firewall reloads and reachable from a container on the node, that a ma
 enrols through the openings before and after a reload and a reboot, and that after the flip the
 declared port is open and the undeclared one closed.
 
+### It filters what arrives from outside, and not what the machine's own guests send
+
+*2026-09-28, preparing the control-node's convergence —
+[issue 141](../../04-ISSUES/141-the-forward-chain-does-not-follow-the-modules/00-report.md), settled by
+[ADR 0140](../../02-DECISIONS/0140-the-filter-constrains-what-arrives-from-outside.md), which replaces
+[ADR 0137](../../02-DECISIONS/0137-a-machine-says-which-networks-it-routes.md) and
+[ADR 0139](../../02-DECISIONS/0139-a-network-is-forwarded-because-a-module-declared-it.md).*
+
+Traffic passing through a machine is filtered, because a container's published port is traffic passing
+through rather than traffic arriving at the machine itself. Having blocked it, the filter then had to
+let the machine's own containers reach outward again — and it did that by listing the address ranges
+they sit on. Two of those ranges were constants in this repository's code, and the rest were typed by an
+operator after the flip had already cut a workstation's containers off from everything.
+
+**The list was the mistake, not its contents.** A constant describes one machine. A typed range goes
+stale and cannot tell a network the mesh made from one a predecessor left behind — on the control-node,
+six ranges fall outside the constants and two of the six belong to services the mesh does not run. The
+attempt to generate the list from the modules put half the rule set on the machine and made the
+derivation advisory. Three records, one list.
+
+**And the mesh has no position on a container reaching outward.** §4 exists to say which port is open
+and to whom, which is about what arrives. A container of this machine's own opening a connection
+somewhere is not a port opened to anybody, and the addresses it might do that from are the machine's
+internal plumbing, which the mesh neither owns nor can know.
+
+So the filter constrains what arrives from **outside** the machine and says nothing about what did not.
+Traffic passing through is allowed unless it came in on one of the machine's outward links, and then
+only where a declared endpoint's reach admits it (§6). The machine says which of its links face
+outside — one fact it reports, like the kind of firewall it found and the tunnel it carries, not a
+setting and not a list of addresses. It does not change when a module is added or removed, which is the
+whole difference from what it replaces. A machine that has reported no outward link is sent no filter
+at all, and keeps the one it has, because a rule written around a link with no name is a rule set that
+does not load — a machine filtering nothing while its unit reports success.
+
+Ports go on following the modules exactly as before: assign a module to a machine and the port its
+assignment says it reaches on opens. Nothing about a network is said anywhere, by anybody.
+
+*How it is checked:* a bed converges a machine carrying containers on several networks, none of them
+named in any setting, and each reaches outward afterwards — which fails against the previous behaviour,
+where the same flip cut them off, and is how it was written; a network made *after* the last declaration
+needs no new filter; a declared port is reachable from off the private network and an undeclared one is
+not; no address of a machine's own networks appears in a rendered filter, asserted on the text; and a
+machine reporting no outward link is refused in the control plane with its existing filter left alone.
+
 ## 5 — Certificates
 
 **Two authorities, kept separate on purpose.**
@@ -710,6 +756,60 @@ that verifies against the internal root and nothing else — which cannot succee
 first reached the name to certify it*
 ([ADR 0066](../../02-DECISIONS/0066-public-routing-is-name-agnostic.md)).
 
+## 6 — One statement behind exposure, filtering and certificates
+
+*2026-09-28, preparing the control-node's convergence —
+[issue 140](../../04-ISSUES/140-an-endpoints-reach-is-not-declared/00-report.md), settled by
+[ADR 0138](../../02-DECISIONS/0138-an-assignment-binds-an-endpoint-and-says-how-far-it-reaches.md).*
+
+The three sections above each decide, independently, how far a service reaches. §3 composes a name
+from a label and the node's domain. §4 opens a port to the source a listen named. §5 certifies the
+names that exist, from whichever authority the proxy holds. Each is coherent on its own, and together
+they mean **reachability is never stated anywhere** — it is the sum of three derivations, and a sum is
+not something anyone can review or refuse.
+
+What that costs, measured: an identity provider holding a public certificate valid 90 days and an
+internal one valid 24 hours, neither asked for by any assignment, because both names existed and a
+proxy certifies what it serves. And an endpoint that is not routed — git over ssh — which can be
+spoken about only in the filter's vocabulary, so *this must be reachable from outside* is a setting
+exactly one mechanism reads.
+
+**An endpoint is the thing that was missing.** A module declares named endpoints: one port it serves,
+what it is for, and what it would serve that to absent any instruction. A route contribution names an
+endpoint rather than repeating a port number. An assignment — which is where a module's configuration
+lives ([ADR 0046](../../02-DECISIONS/0046-a-module-configuration-is-its-assignments-not-its-manifest.md))
+— then binds each endpoint to a machine port and says how far it reaches.
+
+One value, three readers:
+
+| reach | the filter opens | the proxy serves | the certificate comes from |
+|---|---|---|---|
+| `internal` | the machine port, to the private network | the internal name | the mesh's own authority |
+| `public` | the machine port, to anywhere | the public name | the public authority |
+| `both` | the machine port, to anywhere | both names | each name's own authority |
+
+**An endpoint that is not routed is reached and never named.** No route contribution means no name is
+composed and no certificate requested, while the filter still acts on it. That is the case the model
+could not express at all, and it is the ordinary case for anything that is not HTTP.
+
+**Nothing moves until an assignment says so.** An endpoint whose assignment is silent keeps the
+default its manifest states, so every machine already converged renders exactly as it does today —
+the same property §4 needed when a machine gained a way to say which networks it routes.
+
+This is what the certificate questions were waiting for. Which authority signs a name, whether a name
+may appear in a public issuance log, and what must be trusted where are all answerable once an
+endpoint says whether it is internal — and unanswerable while the proxy decides by composing every
+name it can. It is also the fact
+[issue 139](../../04-ISSUES/139-an-internal-route-name-resolves-to-the-consumers-node/00-report.md)
+needs: an internal name should be composed from the machine serving the endpoint, which is the
+assignment that bound it.
+
+**How it is checked** is stated with the decision: one module with two endpoints of differing reach
+asserted per chain body; the names and the certificate requests following the reach and failing
+against today's behaviour, where both are always composed; an unrouted endpoint filtered and never
+named; an assignment naming an endpoint the module does not declare refused where it is said; and a
+silent assignment rendering byte-identically to today.
+
 ## What this removes
 
 The list is worth having in one place, because it is most of the argument:
@@ -769,7 +869,7 @@ where a found tunnel is left running beside the mesh's; where it is adopted ther
 The guard admits the mesh's ports from that one interface, and the predecessor's peers arrive on
 it.
 
-*2026-09-27, [ADR 0119](../../02-DECISIONS/0119-a-taken-tunnels-predecessor-is-retired.md).* The
+*2026-09-27, [ADR 0127](../../02-DECISIONS/0119-a-taken-tunnels-predecessor-is-retired.md).* The
 found configuration is kept only until the take is proven — the found unit down, the mesh's
 interface up and handshaking with a peer. Then it is removed from where the found unit reads it
 (its original stays kept), the hold ends, and the predecessor's tunnel cannot be raised again by

03-DESIGN/01-to-be/18-building-a-module.md

@@ -5,8 +5,9 @@ code:
   - mesh-controller cmd/mesh-builder
   - mesh-controller internal/builder
   - mesh-catalog modules/builder
-updated: 2026-09-25
+updated: 2026-09-29
 decisions:
+  - 02-DECISIONS/0142-the-mesh-delivers-its-own-components-as-binaries.md
   - 02-DECISIONS/0111-a-build-source-is-on-the-git-seat-or-external.md
   - 02-DECISIONS/0097-a-vendor-image-is-a-declared-build-input.md
   - 02-DECISIONS/0096-an-upstream-image-is-copied-between-registries.md
@@ -263,3 +264,27 @@ ships one and wrong for code the mesh built, which has no unit until the mesh wr
 
 **Tools, hooks and consumers are not further modes**, which is the test of whether three is the
 right number: they are loaded by a tool host, and a tool host is a process that stays up.
+
+## The builder compiles the languages the mesh is written in
+
+*2026-09-29 —
+[ADR 0142](../../02-DECISIONS/0142-the-mesh-delivers-its-own-components-as-binaries.md).*
+
+The toolchain list was typescript and python, and only typescript had a base module in the catalogue.
+Meanwhile the control plane — written in the language this project is mostly written in — was built as
+an image from a hand-written Dockerfile, which is the per-repository incantation this whole mechanism
+exists to abolish.
+
+So the list gains Go, with a base module providing the compiler exactly as typescript has one. The
+obligation the list's own comment warns about — an SDK carrying the broker client, the event envelope
+and tool serving — attaches to a **module** written in a language, not to the language being
+compilable. The mesh's own components are not modules in that sense; the host is what applies modules.
+
+**And an artifact says what it targets.** A compiled binary is per operating system, pinned at link
+time, and a toolchain deliberately accepts nothing from the module — anything a module could override
+there it would be writing a Dockerfile to override. The target is therefore a property of the artifact,
+not of the recipe: one artifact declared per target, one build each.
+
+A component's version stops being stamped in at link time. It is unpacked into a directory named for
+its version, so it reads its version from its own path, and a build no longer has to know what it will
+be called.

03-DESIGN/01-to-be/19-the-module-protocol.md

@@ -3,12 +3,13 @@ layer: to-be
 status: proposed
 code:
   - mesh-sdk src
-  - mesh-tools src/broker-amqp.ts
+  - mesh-tools src/broker-nats.ts (and broker-amqp.ts until the rollout)
   - mesh-controller internal/link
 updated: 2026-09-26
 decisions:
   - 02-DECISIONS/0095-the-control-plane-is-the-way-to-ask-a-module.md
   - 02-DECISIONS/0106-the-bus-is-nats.md
+  - 02-DECISIONS/0128-the-mesh-bus-is-required-not-ambient.md
   - 02-DECISIONS/0116-the-bus-is-built-in-five-steps.md
   - 02-DECISIONS/0074-the-wire-is-specified-not-the-types.md
   - 02-DECISIONS/0039-what-the-sdk-holds-and-refuses.md
@@ -25,26 +26,17 @@ language and nothing more ([ADR 0074](../../02-DECISIONS/0074-the-wire-is-specif
 This is a specification, so it says what is required rather than how anything is arranged. Where it
 describes current behaviour that is *not yet* specified-and-conformed, it says so.
 
-> **The wire below is the bus being replaced.** *2026-09-26.*
-> [ADR 0106](../../02-DECISIONS/0106-the-bus-is-nats.md) moved the mesh's bus to NATS. Everything
-> in this document that names an exchange, a queue or a routing key — the event exchanges, the
-> durable `<node>.<module>.events` queue, the shared `serve.<key>` queue — describes the transport
-> being retired, and the conformance fixtures were captured against it.
+> **Rewritten onto NATS, 2026-09-26** (step 3 of
+> [ADR 0116](../../02-DECISIONS/0116-the-bus-is-built-in-five-steps.md)). What
+> [ADR 0074](../../02-DECISIONS/0074-the-wire-is-specified-not-the-types.md) decided is untouched:
+> a floor plus independent capabilities, an implementation legitimate when it claims less,
+> identity from the sealed credential, at-least-once with dedup on `x-event-id`, and conformance
+> as executable fixtures rather than prose. What changed is the transport beneath all of it —
+> exchanges and queues became subjects and streams. The envelope keeps its shape
+> ([ADR 0042](../../02-DECISIONS/0042-the-shape-of-an-event-on-the-wire.md)).
 >
-> What does **not** change is this document's model, which is the part ADR 0074 decided: a floor
-> plus independent capabilities, an SDK that implements what it claims and is legitimate when it
-> claims less, identity taken from the sealed credential rather than the environment, at-least-once
-> with dedup on `x-event-id`, and conformance as executable fixtures per capability rather than
-> prose. The envelope keeps its shape ([ADR 0042](../../02-DECISIONS/0042-the-shape-of-an-event-on-the-wire.md));
-> it becomes the message body.
->
-> Rewriting the wire sections onto the subjects and streams of
-> [design 25](25-the-bus-on-nats.md) §2–§3, and recapturing the fixtures there, is **step 3 of
-> [ADR 0116](../../02-DECISIONS/0116-the-bus-is-built-in-five-steps.md)**. Until that lands, read
-> the sections below for what two implementations may not disagree *about*, and design 25 for what
-> they will disagree about it *on*. A specification that silently described a retired transport
-> would be worse than an absent one, because it reads as current — hence this note rather than a
-> quiet edit.
+> Statements here marked *verified* were checked against a running server while the runtime's
+> client was written, not reasoned from documentation.
 
 ## The shape of it
 
@@ -70,22 +62,39 @@ document:
 
 | field | is | required |
 |---|---|---|
-| `url` | an `amqps://` URL carrying the account's user and password | yes |
-| `fingerprint` | sha256 of the certificate the broker must present | yes for a scoped account |
+| `url` | a `tls://` URL for the bus, with the account's user and password | yes |
+| `fingerprint` | sha256 of the certificate the bus must present | yes for a scoped account |
 | `node` | the machine this account was issued for | yes for a scoped account |
 | `module` | the module this account was issued for | yes for a scoped account |
 
 A plain string rather than a document is a **bootstrap URL** — unscoped, for the moment before a
 mesh can issue anything. An implementation accepts both and must not treat the second as ordinary.
 
+**`node` and `module` are not decoration: every subject an implementation touches is derived from
+them.** Its own namespace is `mesh.mod.<module>`, its consumer is `<node>_<module>`, its inbox is
+its own. So a credential without them is refused rather than guessed at — an implementation that
+fell back to an environment variable would let anything on the machine decide which module it is,
+which is what the identity rule below exists to prevent.
+
+The credential itself is fetched, never carried in a declaration: a declaration is persisted as
+state and a sealed secret in a stream is an archive rather than a moment
+([design 29](32-what-a-module-declares.md) §10).
+
 ### Connecting
 
 - The connection **pins the fingerprint**. It does not trust a certificate authority, and it does
-  not skip verification. A broker presenting a different certificate is refused, whatever else is
+  not skip verification. A bus presenting a different certificate is refused, whatever else is
   true of it.
-- A scoped account **does not declare exchanges**. The foundation owns them; an account that may
-  declare one is an account that may create a parallel mesh by typo.
-- An implementation **declares its own queue** and nothing else.
+- **The certificate must also carry a name the bus is dialled by.** *Verified:* the NATS client
+  exposes no hook to replace hostname verification, so pinning no longer makes it redundant the
+  way it did on AMQP — the pin happens before dialling and the library's own name check happens
+  beside it. A certificate without a matching subject-alternative name is refused at connect, by
+  a library error rather than by anything the mesh says.
+- An implementation **creates nothing on the bus**: not a stream, not a consumer, not a subject.
+  Streams and durable consumers are the controller's alone ([design 25](25-the-bus-on-nats.md)
+  §3), and a module's account cannot reach the JetStream API to make one. An implementation binds
+  the consumer the mesh created for it, and if it is absent that is a mesh that has not finished
+  assigning the module, not something for the module to fix.
 
 ### Identity
 
@@ -100,26 +109,49 @@ the credential disagree, the credential wins and the variable is overwritten.
 
 ## Capability: events
 
-### The exchanges
+### The subjects
 
-| exchange | carries |
+| subject | carries |
 |---|---|
-| `mesh.events` | every event |
-| `mesh.events.dead` | what could not be handled |
+| `mesh.mod.<module>.event.<key>` | an event that module emitted |
+| `mesh.seat.<seat>.event.<verb>` | an event the holder of that role emitted |
 
-### The queue
+Both are captured by the `EVENTS` stream. **An event's source is enforced rather than claimed**: a
+module's account may publish only into its own namespace, so `x-source` cannot disagree with where
+the message arrived from.
 
-One **durable** queue per consumer, named `<node>.<module>.events`, with as many bindings as the
-module has patterns. Durable because an event emitted while a module is restarting is exactly the
-one that must not be lost.
+**The `event` token is load-bearing.** A module's namespace also carries its tool calls
+(`mesh.mod.<module>.tool.<tool>`), and a stream is defined by a subject filter — without the token
+the events stream would capture every tool invocation in the mesh, and a tool call must never be
+persisted.
 
-**A message matching two bindings is delivered once**, so an implementation must match the routing
-key against its own patterns locally to decide which handlers run. An implementation that ran every
-handler whose exchange binding matched would run the wrong one.
+### The consumer
+
+One **durable consumer** per module, named `<node>_<module>`, carrying one filter per pattern the
+module consumes. Durable because an event emitted while a module is restarting is exactly the one
+that must not be lost.
+
+**Created by the controller, bound by the implementation.** A module declares what it reacts to
+and never how delivery works, so it does not name its consumer, does not choose its ack policy or
+delivery limit, and cannot misconfigure them.
+
+*Verified, and it is a trap:* a durable name **may not contain a dot**, while the subject a
+consumer acknowledges on is `$JS.ACK.<stream>.<consumer>.…` — two names joined by one. An
+implementation that treats them as a single string reads correctly in a permission list and is
+refused as a consumer name. Left wrong, the symptom is every message redelivered forever while
+the permissions look right.
+
+**One consumer may carry filters wider than one handler's pattern**, because a module subscribing
+twice gets one consumer with both. So an implementation still matches the key against its own
+patterns locally to decide which handlers run — and **acknowledges a message no handler wanted**,
+or it is redelivered until it expires.
 
 ### The envelope
 
-Headers ride as AMQP headers. The body is JSON.
+Headers ride as **NATS headers**; the body is JSON, and the body alone. *Verified:* the payload is
+the event's `body`, not the whole envelope re-encoded — an implementation that nested the envelope
+would pass every one of its own tests and agree with no other, which is the exact failure the
+conformance fixtures exist to catch. The key is recovered from the subject, not carried twice.
 
 | header | is | required |
 |---|---|---|
@@ -140,6 +172,11 @@ breaking change for everybody.
 At-least-once. **Deduplication is on `x-event-id`**, which only the emitter can produce — a
 consumer cannot tell a redelivery from a second event any other way.
 
+On NATS the id does double duty: an implementation passes it as the publish's message id, so the
+**server** also refuses a duplicate inside its window. That narrows the window in which a
+consumer has to deduplicate; it does not remove the requirement, because the window is finite and
+a redelivery after it is still a redelivery.
+
 ### What is true, checked (2026-09-16)
 
 Go emits all five required headers; the SDK requires exactly those. `x-causation-id` and `x-schema`
@@ -154,22 +191,30 @@ version to declare.
 
 A module's tools are its operator-facing surface.
 
-- A tool is served from a **shared durable queue**, `serve.<key>`. Shared, so several runtimes
-  serving one tool compete for a call rather than each answering it.
-- A call is request and reply. The reply returns through the RPC exchange `mesh.rpc`, keyed by the
-  caller's own reply queue — **not** through the default exchange, which would let a caller publish
-  into any queue on the broker.
-- A caller needs a **reply queue**, and that is what a module's scoped account may not declare
-  ([issue 049](../../04-ISSUES/049-a-module-can-serve-tools-and-nothing-can-call-them/00-report.md)).
-  So a module may serve tools and may not call them.
-- **The control plane is the way to ask**
-  ([ADR 0095](../../02-DECISIONS/0095-the-control-plane-is-the-way-to-ask-a-module.md)):
-  `ask <module> <tool> [json]` publishes on `mesh.rpc` under `<module>.<tool>` with a private reply
-  queue bound under its own name, and prints the answer as the module gave it. A module declares
-  nothing about being asked — serving a tool is being askable through the control plane. A
-  module-to-module call, if one is wanted, is a grant like any other and a later decision.
-  *How it is checked:* a tools-only bed asks a served tool through the control plane and asserts
-  an answer arrived, where a timeout would read differently.
+- A tool is served on `mesh.mod.<module>.tool.<tool>`, with a **queue group** — so several
+  runtimes serving one tool compete for a call rather than each answering it.
+- A call is request and reply on **core NATS, never a stream**. A tool call is not persisted: a
+  lost one is a timeout the caller already handles, and a stream of them would be the mesh's most
+  voluminous and least valuable traffic competing for retention with the messages that matter.
+- The reply goes to the inbox the request carries. A responder may answer it because its account
+  is granted **`allow_responses`** — one reply to the subject of a message it actually received,
+  and nothing wider. That is what makes a per-account inbox prefix workable: no user is ever
+  granted `_INBOX.>`, so without it a responder could not reach the caller at all.
+- **A module may now call a tool, which on AMQP it could not.** *Verified:* two modules on
+  separate connections, one serving and one calling, with an answer returned and a throwing
+  handler reaching the caller as an error rather than a timeout.
+  [Issue 049](../../04-ISSUES/049-a-module-can-serve-tools-and-nothing-can-call-them/00-report.md)
+  recorded the old limit — a scoped account could not declare the reply queue a caller needs —
+  and [ADR 0095](../../02-DECISIONS/0095-the-control-plane-is-the-way-to-ask-a-module.md) routed
+  every ask through the control plane because of it. **That constraint is gone**, and each
+  account's own inbox prefix replaces it.
+
+  ADR 0095 is not thereby reversed: the control plane remains *a* way to ask, and a person asking
+  a module should still go through it. What changes is that "a module-to-module call, if one is
+  wanted, is a later decision" is no longer a question about *capability*. It is a policy
+  question, and the answer the mesh already has is `uses`: a module declares the seat it calls,
+  and the permission follows the declaration.
+- A module declares nothing about being asked — serving a tool is being askable.
 
 ---
 

03-DESIGN/01-to-be/23-choosing-a-provider.md

@@ -6,7 +6,7 @@ updated: 2026-09-25
 decisions:
   - 02-DECISIONS/0084-which-provider-serves-a-consumer.md
   - 02-DECISIONS/0027-a-provision-names-what-the-consumer-is-coupled-to.md
-  - 02-DECISIONS/0110-a-seat-is-a-module-assignment-from-a-closed-set.md
+  - 02-DECISIONS/0126-a-module-declares-its-own-seats.md
 ---
 
 # 23 — Choosing a provider
@@ -54,7 +54,7 @@ to that provider and not to whichever one is nearest.
 **A seat names the mesh's one provider of a kind.** Where a seat delivers the provision, its holder
 answers for it when several providers exist and the consumer named none. That is not picking: the
 choice was made once, mesh-wide, by assigning the holder, rather than once per consumer by naming it
-([ADR 0110](../../02-DECISIONS/0110-a-seat-is-a-module-assignment-from-a-closed-set.md),
+([ADR 0126](../../02-DECISIONS/0126-a-module-declares-its-own-seats.md) (superseding [ADR 0110](../../02-DECISIONS/0110-a-seat-is-a-module-assignment-from-a-closed-set.md)),
 [26 — The seats](26-the-seats.md)). A named provider still wins over the seat, because a consumer
 coupled to particular contents has said so.
 

03-DESIGN/01-to-be/25-the-bus-on-nats.md

@@ -1,15 +1,16 @@
 ---
 layer: to-be
-status: proposed
+status: in-progress
 code:
   - mesh-controller internal/link (to be replaced)
   - mesh-host internal/link (to be replaced)
   - mesh-tools src/broker-amqp.ts (to be replaced)
   - mesh-catalog modules/nats (to be written)
   - mesh-sdk src (the protocol's NATS binding, step 3)
-updated: 2026-09-26
+updated: 2026-09-27
 decisions:
   - 02-DECISIONS/0106-the-bus-is-nats.md
+  - 02-DECISIONS/0131-everything-on-the-mesh-speaks-to-the-broker-seat.md
   - 02-DECISIONS/0116-the-bus-is-built-in-five-steps.md
   - 02-DECISIONS/0074-the-wire-is-specified-not-the-types.md
   - 02-DECISIONS/0079-the-foundation-seats-are-named-after-their-servers.md
@@ -17,6 +18,8 @@ decisions:
   - 02-DECISIONS/0043-a-module-broker-account-is-scoped-by-emits-and-consumes.md
   - 02-DECISIONS/0083-one-push-leaves-the-mesh-consistent.md
   - 02-DECISIONS/0039-what-the-sdk-holds-and-refuses.md
+  - 02-DECISIONS/0129-a-seat-carries-the-protocol-of-its-role.md
+  - 02-DECISIONS/0130-the-predecessor-is-ending-and-its-broker-goes-with-it.md
 ---
 
 # 25. The bus on NATS
@@ -29,19 +32,37 @@ Prose and diagrams only; no configuration is pasted.
 
 ## 1. What the bus is for
 
-The bus carries five kinds of traffic today, and this design keeps the five, renaming nothing a
-module can see:
+**The bus is where the mesh happens.** Not a transport the mesh sends things over — the place a
+module is reachable at all, where a role is addressed without knowing who holds it, where the
+mesh's own state lives, and where what a module may say is decided by what it declared.
 
-| Traffic | Today | Guarantee it needs |
+| Traffic | Shape | Guarantee it needs |
 |---|---|---|
-| **control** — a node's report, its heartbeat, a build's outcome, an enrolment | queues `control`, `.upgrades`, `.catchup` | nothing lost while the store restarts; retried; in order per node |
-| **declarations** — the controller tells a node what to be | queue `node.<name>` | the node gets the newest; a stale one is never applied |
-| **builds** — the controller asks the build machine to build | queue `builds` | at least once, one builder at a time |
-| **events** — a module says something happened | topic exchange `mesh.events`, keys `<module>.<event>` | delivered to every consumer that declared it; dead-lettered when it cannot be |
-| **tools** — one module or person asks another's tool a question | exchange `mesh.rpc`, per-tool service queues `serve.<module>.<tool>` | one answer, from one server, or a timeout |
+| **control** — a node's report, a build's outcome, an enrolment | job | nothing lost while the store restarts; retried; in order per node |
+| **heartbeat** — a node saying it is alive | fire and forget | none; a lost one is the next one |
+| **declarations** — the controller tells a node what to be | state | the node gets the newest; a stale one is never applied |
+| **builds** — work for the build machine | job | at least once, one worker at a time |
+| **events** — a module says something happened | 1:many | delivered to every consumer that declared it; dead-lettered when it cannot be |
+| **tools** — a module or a person asks another's tool | request/reply | one answer, from one server, or a timeout |
+| **work to a role** — a module submits to a capability without knowing who provides it | job | exactly one holder does it; it queues while nobody does |
 
-The sdk's contract — `request`, `handle`, `publish`, `subscribe`, `close` — is the whole surface a
-module sees, and it does not change ([ADR 0039](../../02-DECISIONS/0039-what-the-sdk-holds-and-refuses.md)).
+The last two rows are the ones worth dwelling on, because they are not messaging in the sense of
+carrying bytes from A to B. **A role is addressable**, so a caller names the capability and never
+the module or the node — and the implementation can be replaced under it without a caller
+changing ([ADR 0126](../../02-DECISIONS/0126-a-module-declares-its-own-seats.md)). That is a
+property of the mesh's architecture that happens to be expressed in subjects.
+
+And more of the mesh lands here as it is built: conditions and observed state in key-value
+buckets that anything may watch, the server's own advisories becoming observations like any other
+([research 017](../../01-RESEARCH/017-a-mesh-that-heals-itself/00-overview.md)), and a person's
+client speaking the bus directly rather than through a surface built over it (§7). None of that
+is a message being moved; all of it is the bus being the mesh's centre.
+
+**What a module sees of it is small and derived.** It declares what it emits, consumes, serves
+and uses, and the subjects, streams, consumers and permissions all follow from that
+([design 29](32-what-a-module-declares.md)). The sdk's contract — `request`, `handle`, `publish`,
+`subscribe`, `close` — is the whole surface, and it does not change
+([ADR 0039](../../02-DECISIONS/0039-what-the-sdk-holds-and-refuses.md)).
 
 ## 2. Subjects
 
@@ -52,14 +73,30 @@ permissions are expressed as which branches of it that account may publish to an
 mesh.control.<node>.report        a node's report              (JetStream: CONTROL)
 mesh.control.<node>.alive         heartbeat                    (core, no persistence)
 mesh.control.enrol                an enrolment request         (JetStream: CONTROL)
-mesh.control.built                a build's outcome            (JetStream: CONTROL)
 mesh.node.<node>.declare          a declaration for a node     (JetStream: NODES, last-per-subject)
-mesh.build.request                work for the build machine   (JetStream: BUILDS, work queue)
-mesh.events.<module>.<event>      an event                     (JetStream: EVENTS)
-mesh.tools.<module>.<tool>        a tool invocation            (core request/reply)
+mesh.mod.<module>.event.<event>   an event                     (JetStream: EVENTS)
+mesh.mod.<module>.tool.<tool>     a tool invocation            (core request/reply)
+mesh.seat.<seat>.accept.<verb>    work submitted to a role     (JetStream: per-seat work queue)
+mesh.seat.<seat>.event.<verb>     a role's own event           (JetStream: EVENTS)
+mesh.seat.<seat>.tool.<verb>      a role's tool                (core request/reply)
 mesh.ask.<node>.<command>         the controller's command api (core request/reply)
 ```
 
+**Revised 2026-09-27** ([ADR 0129](../../02-DECISIONS/0129-a-seat-carries-the-protocol-of-its-role.md)):
+**`mesh.build.request`, `mesh.control.built` and the BUILDS stream are gone.** A build is work submitted to a role, and the
+mesh already has a shape for that — a seat's `accept` subjects, on a work queue with a queue group of
+holders, which is what a build queue shared by several machines *is*. Keeping a second mechanism for it
+meant two things to reason about and two places for a permission to be wrong. A build's outcome is the
+seat's own event — which is why the control branch loses its copy too: one publish reaches whoever
+asked, the controller that records it and the catalogue that places it — the fan-out a shared exchange gave for free, as a derived subject rather than a
+configured topology.
+
+**Revised 2026-09-26** ([design 29](32-what-a-module-declares.md)): a module's events and tools
+moved from `mesh.events.*` / `mesh.tools.*` into one namespace per module, `mesh.mod.<module>.>`,
+so a module's authority over its own name is a single subject pattern the server enforces — and
+each carries a **kind token**, without which an events stream's filter would capture tool calls.
+Seats are the same shape, one namespace per role.
+
 Two things this buys over the exchanges: **request/reply is native** — a tool call is one
 `request` on `mesh.tools.<module>.<tool>` answered by whichever runtime serves it (a queue group per
 tool, so several nodes may serve one tool); and **a declaration is last-per-subject** — the NODES
@@ -69,7 +106,14 @@ exactly the current declaration and nothing older. That is the wire-level answer
 *is* the order, and a node that sees sequence n refuses n−1 by construction.
 
 **A reply-to travelling through a JetStream stream is carried in the payload, never in the
-transport `Reply` field.** Revision, first review: core NATS request/reply sets the requester's
+transport `Reply` field.** *Verified against a running server, 2026-09-27*: a caller published
+asking for a reply to `_INBOX.LCr3M83q…`, and the consumer saw a `Reply` field of
+`$JS.ACK.PROBE.probe_consumer.1.1.1…`. The address is replaced, not merely at risk — so the
+payload-borne reply subject below is necessary rather than defensive, and the check is a test
+rather than a note, because a future server that stopped doing this would leave enrolment
+working and the reason for the field quietly becoming folklore.
+
+Revision, first review: core NATS request/reply sets the requester's
 ephemeral inbox as the message's `Reply` field, and a plain responder answers it directly — but a
 message a JetStream consumer delivers has already had that field claimed for the consumer's own
 ack address (`$JS.ACK.<stream>.<consumer>...`), so by the time the controller (§3's CONTROL
@@ -89,10 +133,9 @@ Core NATS is at-most-once. Everything the mesh must not lose lives in a JetStrea
 
 | Stream | Subjects | Retention | Why |
 |---|---|---|---|
-| CONTROL | `mesh.control.>` except `alive` | work queue, one consumer (the controller), explicit ack | the store-window guarantee ([ADR 0083](../../02-DECISIONS/0083-one-push-leaves-the-mesh-consistent.md)): the controller `nak`s with a delay while its store is away and the message is redelivered; nothing is dropped |
+| CONTROL | `mesh.control.>` except `alive` (a build's outcome moved to its seat, ADR 0121) | work queue, one consumer (the controller), explicit ack | the store-window guarantee ([ADR 0083](../../02-DECISIONS/0083-one-push-leaves-the-mesh-consistent.md)): the controller `nak`s with a delay while its store is away and the message is redelivered; nothing is dropped |
 | NODES | `mesh.node.>` | last per subject | one declaration per node, always the newest |
-| BUILDS | `mesh.build.>` | work queue, explicit ack | at least once; a builder that dies mid-build has its message redelivered |
-| EVENTS | `mesh.events.>` | limits (age, size), durable consumer per subscribing module | a subscriber that was down catches up; after `max-deliver` attempts the advisory feeds `mesh.events.dead` (its own small stream) |
+| EVENTS | `mesh.mod.*.event.>` | limits (age, size), durable consumer per subscribing module | a subscriber that was down catches up; after `max-deliver` attempts the advisory feeds `mesh.events.dead` (its own small stream) |
 
 Tool calls and heartbeats stay on core NATS: a lost heartbeat is the next heartbeat; a lost tool
 call is a timeout the caller already handles.
@@ -100,6 +143,33 @@ call is a timeout the caller already handles.
 Streams and consumers are objects the controller creates at genesis and asserts on start; a module
 declares nothing about them. The controller is the only writer of stream definitions.
 
+### The store window, and what moving it into the server changes
+
+The guarantee ([ADR 0083](../../02-DECISIONS/0083-one-push-leaves-the-mesh-consistent.md)) is
+that a push the controller cannot record because its store is restarting is **held and retried** —
+never dropped, never falsely acknowledged. Here that is a `nak` with a delay: the server holds
+the message and redelivers it, so the controller keeps no list of parked messages and one that
+restarts mid-window loses nothing it was holding.
+
+**That is a plain win, and it introduces one problem worth naming.** Holding a delivery in memory
+let the controller drop an older report when a newer one for the same node arrived, because
+acting on the older after the newer would undo the newer. A `nak`ed message belongs to the server
+and comes back whatever happened meanwhile — so the older report is redelivered *after* the newer
+was applied.
+
+The answer was already in the message. A report carries the **digest of the declaration it is
+about**, which exists because an earlier attempt to order reports by time lost the race it
+invited: an apply that began under the previous declaration finishes after the next is sent, and
+its report reads as newer than the send. Clocks cannot answer *which*.
+
+So supersession stops being something the controller remembers and becomes something it checks —
+a report whose digest is not the one outstanding for that node is acknowledged without being
+acted on. The same shape as a node refusing a superseded declaration by sequence
+([issue 107](../../04-ISSUES/107-a-declaration-carries-no-order/00-report.md)): **ordering settled
+by what a message says, not by when it arrived.** And staleness is checked before the store is
+waited on, so a redelivery that lost its race does not hold a slot in the window that a current
+message needs.
+
 ## 4. Accounts
 
 [ADR 0043](../../02-DECISIONS/0043-a-module-broker-account-is-scoped-by-emits-and-consumes.md) says a
@@ -128,19 +198,56 @@ expresses this exactly, per subject, and better than a vhost could:
     permissions name only that one prefix, for the reply to any request it makes and nothing
     wider. First review found the account note without this and read it as "any user may
     subscribe any inbox" — which was accurate against the text as it stood.
+
+    **And a scoped inbox needs `allow_responses`, or nothing can answer.** Revision, found while
+    composing the first real configuration: the rule above scopes each user's inbox to itself,
+    which is right — and leaves a responder unable to reply, because the answer goes to the
+    *caller's* inbox, which the responder has no permission for. The two ways out are granting
+    every responder `_INBOX.>`, which is exactly the blanket grant this bullet refuses, or NATS's
+    own `allow_responses`: the server permits one reply to the reply-subject of a message the user
+    actually received, within a TTL, and nothing else. So authority to answer is bounded by having
+    been asked, and only principals that serve something are granted it — a pure consumer gets
+    nothing. Without this the scoping is not merely incomplete: every tool call in the mesh times
+    out, and the permission list looks correct while it happens.
 - **One user per module per node**, as today, with publish permissions
   `mesh.events.<module>.<event>` for each emit, `mesh.tools.<module>.>` to serve its tools, its
   own ack-reply subject for each durable consumer it holds, and its own inbox prefix; subscribe
   permissions for each consumed event's subject, its tool subjects, and that same inbox prefix.
   Nothing else. A module that tries to publish outside its emits is refused by the server, not by
   convention.
-- **The controller's user** owns `mesh.control.>`, `mesh.node.>`, `mesh.build.>` and the streams.
+- **The controller's user** owns `mesh.control.>`, `mesh.node.>` and the streams, and may submit work
+  to the seats the mesh's own flows use — a build, for one (ADR 0121).
   **A host's user** may publish its own `mesh.control.<node>.>` and subscribe its own
   `mesh.node.<node>.declare` — and nothing of any other node's.
 - **A person's user** (§7) is a module-shaped user with permissions on the tool subjects it may
   invoke, issued and revoked by the controller like any account.
 
-**Accounts are configuration, not API calls.** The controller composes the server's user list and
+**The server does not verify client certificates, and TLS is still required.** *Revision,
+2026-09-27, found by building the module's image and connecting to it as a host would.* The first
+composed configuration said `verify: true`, which makes the server demand a **client** certificate —
+and nothing in the mesh presents one. A host pins this server's exact certificate and authenticates
+with the password the mesh minted ([ADR 0004](../../02-DECISIONS/0004-a-node-and-how-it-joins.md)),
+and a module's runtime does the same. With it on, every connection in the mesh dies at the TLS
+handshake before any password is looked at, and the error — "client didn't provide a certificate" —
+reads as a fault in the client rather than in the bus's configuration. The `tls` block is what makes
+TLS required; `verify` only decides whether client certificates are checked. What is given up is a
+second factor the mesh has no machinery to issue or rotate — a certificate per module per node — and
+what is kept is stronger than a name check in both directions: an exact pin outward, a password
+scoped per user inward. **Mutual TLS is a later question and would need that machinery first.**
+
+**The mesh composes the accounts; the module composes its server.** *Revision, 2026-09-27, while
+building the composition.* An earlier reading of the paragraph below had the controller writing the
+whole file. It writes only the user list. A server's ports, its TLS paths and its store directory
+are properties of the container the module raises — they live in its image and its mounts and change
+when it does — so the module declares its own configuration and `include`s the mesh's half. A
+controller that wrote the whole file would have to be kept in step with a Dockerfile it never sees,
+and a module could not change its own image without the mesh agreeing. Asking for the user list is
+not enough to receive it: the file holds every user's password hash, so the claim on `mesh-broker` is
+what authorises it. And the two files share one directory of necessity — an absolute include path is
+resolved relative to the including file's own directory, so a server given one from elsewhere looks
+for it underneath that directory and refuses to start.
+
+**Accounts are configuration, not API calls.** The controller composes the mesh's user list and its
 permissions into a file the host declares. **How that file reaches the running server is §5's,
 not this one's** — revision, first review: an earlier draft said "reloads" and cited a precedent
 that does not apply to a container (see §5). No management API, no credential travelling through a
@@ -157,9 +264,14 @@ signing hierarchy for nothing.
 
 `nats` is a catalogue module claiming the seat `mesh-broker`
 ([ADR 0079](../../02-DECISIONS/0079-the-foundation-seats-are-named-after-their-servers.md): the seat
-is the server, and the server changes). It declares one container (a single binary; JetStream on a
-named volume), its listening ports — client, TLS, and the monitoring endpoint on loopback — and a
-configuration file the controller composes (accounts, permissions, TLS, JetStream).
+is the server, and the server changes). It declares one container (a single binary; **JetStream on a host
+directory bind, not a named volume** — revision, second review:
+[issue 115](../../04-ISSUES/115-a-named-docker-volume-is-invisible-and-one-flag-from-gone/00-report.md)
+is resolved, and converted the store, the broker and two others away from named volumes for the
+reason it names; the bus's own data is not the place to reintroduce one), its listening ports —
+**the client port, which carries TLS itself** rather than standing beside a plaintext one as the
+AMQP broker's 5671/5672 pair did, and the monitoring endpoint on loopback — and a configuration
+file the controller composes (accounts, permissions, TLS, JetStream).
 
 **How that file's changes reach the running server, corrected on revision.** First review: the
 earlier draft named `reload-on` as the mechanism, citing the container runtime's own trust file as
@@ -186,10 +298,33 @@ same place `modules/gitea/token.ts` keeps its own state rather than asking the h
 The host's only job is what it already does for any directory resource: keep the file's content
 current. Nothing is declared as `reload-on` or `restart-on` for this resource at all.
 
-Its guard is the same rule as the AMQP broker's: the monitoring port is refused from anything but
+Its guard is the same rule as the deprecated broker's: the monitoring port is refused from anything but
 the private network. It is raised at genesis like the store, adopted as a module in the same
-phase. The predecessor's AMQP broker remains a module of its own, `lavinmq-compat`, with a single
-purpose and a retirement condition: no client connected for a period the operator sets.
+phase.
+
+**The deprecated broker is an ordinary module, not a compatibility layer.** Revision, second review
+([ADR 0127](../../02-DECISIONS/0127-amqp-is-a-provision-not-the-bus.md) (superseded by [ADR 0131](../../02-DECISIONS/0131-everything-on-the-mesh-speaks-to-the-broker-seat.md): AMQP is not a provision, and everything speaks to the `mesh-broker` seat)): earlier text here, and
+ADR 0106 before it, called it `lavinmq-compat` — one purpose, the predecessor's clients, and a
+retirement condition of no client connected for a period the operator sets. It is none of those.
+A module may legitimately need an AMQP broker as a **backing service**, the way it needs a
+database, and the provider that answers that is an ordinary module like any other: no seat, not
+foundation, never raised at genesis, installed when something wants it and absent from a mesh
+that does not. There is no retirement condition, because the day its last client disappears is
+not a day anything is waiting for.
+
+**Revised 2026-09-27** ([ADR 0130](../../02-DECISIONS/0130-the-predecessor-is-ending-and-its-broker-goes-with-it.md)):
+**that day is coming.** The predecessor is deprecated — some of it still running, none of it being
+migrated, left to stop rather than moved — so the broker retires once nothing requires `amqp`. Still no
+retirement *condition* and no end-date machinery: a provision with no consumers has its provider
+unassigned, which is the ordinary mechanism and is ADR 0127 being paid off rather than revised. What
+also goes with it is the tooling that reaches this installation's machines remotely, because the
+predecessor's own mesh talks over that broker — so the rollout is driven from the node, or before the
+broker stops.
+
+What is deprecated is AMQP as **the mesh's transport**, which is this whole document. The rule
+that remains is about direction rather than software: *inter-module communication goes over the
+bus.* A module may hold a broker, a database or a cache for itself; it may not use one as a
+channel to another module.
 
 ## 6. Joining: the enrolment handshake
 
@@ -272,7 +407,7 @@ wrong until there is a second mesh. *Ends at: the genesis bed.*
 **Step 2 — adoption puts the broker in its seat.** A mesh already running does not get a foundation
 module by being raised again; it adopts one in place
 ([ADR 0100](../../02-DECISIONS/0100-a-node-in-use-is-adopted-before-it-is-converged.md)). The
-server is raised beside the AMQP broker on its own ports, carrying no mesh traffic yet, and the
+server is raised beside the deprecated broker on its own ports, carrying no mesh traffic yet, and the
 `nats` module is adopted onto it. The seat it claims is **`mesh-broker`**, unchanged — the
 foundation seats are named after the server's role rather than the product
 ([ADR 0079](../../02-DECISIONS/0079-the-foundation-seats-are-named-after-their-servers.md)) for
@@ -333,7 +468,7 @@ itself enforces and a plain client can therefore check:
   watcher-poll interval, without a restart.
 
 **Step 2 — the adoption bed**, a mesh already running that has never had this server:
-- the server is raised beside the AMQP broker on its own ports and the `nats` module is adopted
+- the server is raised beside the deprecated broker on its own ports and the `nats` module is adopted
   onto it in place, holding the data and the configuration it was raised with;
 - the seat it claims is `mesh-broker`, and a second assignment of it anywhere in the mesh is
   refused at resolution — *one per mesh*, as ADR 0079 requires;
@@ -398,8 +533,11 @@ find what changed and why.
 
 **Still open:**
 
-- Whether EVENTS should be one stream or one per emitting module (retention per module vs. one
-  policy). One stream is proposed; the review may disagree.
+- ~~Whether EVENTS should be one stream or one per emitting module.~~ **Closed**
+  ([ADR 0127](../../02-DECISIONS/0127-amqp-is-a-provision-not-the-bus.md) (superseded by [ADR 0131](../../02-DECISIONS/0131-everything-on-the-mesh-speaks-to-the-broker-seat.md): AMQP is not a provision, and everything speaks to the `mesh-broker` seat) (superseding [ADR 0125](../../02-DECISIONS/0125-the-bus-is-the-only-broker.md))): one stream, and not as a
+  preference — the streams the bus is made of are composed as configuration before any module
+  runs, because a provisioner is itself a module that needs a bus account to start. Bootstrapping
+  decides it.
 - The heartbeat interval and the controller's "quiet" threshold on core NATS without persistence —
   the same numbers as today are proposed.
 - Whether the person's client is a catalogue module (runs on an enrolled workstation node) or a

03-DESIGN/01-to-be/26-the-seats.md

@@ -4,13 +4,17 @@ status: implemented
 code:
   - mesh-controller internal/catalogue/seats.go
   - mesh-controller internal/catalogue/resolve.go
+  - mesh-controller internal/inventory/seats.go
+  - mesh-controller internal/inventory/migrations/0039-a-seat-is-held-by-one-assignment-on-record.sql
   - mesh-controller cmd/mesh-controller/seats.go
   - mesh-controller cmd/mesh-controller/source.go
   - mesh-controller internal/inventory/migrations/0032-a-source-may-live-on-a-seat.sql
   - mesh-catalog modules/gitea/module.json
 updated: 2026-09-27
 decisions:
-  - 02-DECISIONS/0110-a-seat-is-a-module-assignment-from-a-closed-set.md
+  - 02-DECISIONS/0131-everything-on-the-mesh-speaks-to-the-broker-seat.md
+  - 02-DECISIONS/0126-a-module-declares-its-own-seats.md
+  - 02-DECISIONS/0128-the-mesh-bus-is-required-not-ambient.md
   - 02-DECISIONS/0111-a-build-source-is-on-the-git-seat-or-external.md
   - 02-DECISIONS/0109-a-package-registry-seat-is-one-per-ecosystem.md
   - 02-DECISIONS/0117-a-machines-uplink-is-a-seat.md
@@ -41,6 +45,31 @@ is refused. A seat makes a role singular, never a module.
 **The seat points at the assignment.** Everything the mesh knows about the holder is what it knows
 about that assignment: the node, the node's settings for the module, and what the module serves.
 
+**Which assignment holds a seat is a fact on record, and changes as one act.** Revision, 2026-09-27
+([ADR 0131](../../02-DECISIONS/0131-everything-on-the-mesh-speaks-to-the-broker-seat.md)). Until
+then the holder was derived — the module that is assigned and claims the seat holds it, and a second
+eligible assignment was refused. That has no way to pass a seat from one holder to the next without a
+moment in which nobody holds it, and the controller finds its own bus through one of these seats: that
+moment took the control plane down for an evening. So the holder is now one row the controller keeps,
+written by a handover — `seat <name> --to <node>/<module>` — that names the seat and the assignment
+taking it over and replaces the previous holder in the same write. Between two handovers the seat has
+exactly one holder, and it is never none.
+
+Three consequences follow. **A seat with no row is held as it always was**: the sole eligible
+assignment holds it, and two eligible ones are refused — so a mesh that has never handed a seat over
+behaves exactly as before, and the row appears the first time somebody does. **With a row, any other
+assignment whose module could hold the seat is eligible and silent**: neither refused nor holding.
+That is what lets the next holder run beside the current one until the handover, which the bus's move
+needs ([28](28-building-the-bus.md), task 5.3). **And a holding is the assignment's**: unassigning the
+holder takes the row with it, so a seat never points at something that is not running anywhere, and
+the seat falls back to derivation rather than to nothing.
+
+The handover refuses what would make the new holder wrong before anything is written: the seat must
+exist, the assignment must exist, and the module must be able to hold the seat — claim it at its scope
+and provide what it delivers, judged against the store's row and not against anything compiled into a
+binary. It does not check that the module is running yet; `push` confirms that afterwards, and a
+handover that could only be recorded after the new holder was up could not be the switch.
+
 **The set is closed.** A seat the mesh does not define is refused wherever it is named, and so is one
 named at the wrong scope. Adding a seat is a decision, recorded, for the reason every addition to the
 host's vocabulary is one: the set is what a person reads to learn what a mesh can have, and an entry
@@ -48,28 +77,55 @@ nobody argued for is an entry nobody can explain.
 
 ## The set
 
-| seat | scope | delivers | typically held by |
-|---|---|---|---|
-| `mesh-controller` | mesh | — | the controller |
-| `mesh-store` | mesh | — | the store the mesh's own records live in |
-| `mesh-broker` | mesh | — | the broker carrying the mesh's own bus |
-| `mesh-vault` | mesh | `secret`, reserved | the vault |
-| `the-artifact-store` | mesh | `artifact-store` | the artifact registry |
-| `the-catalogue` | mesh | — | the catalogue |
-| `npm-package-registry` | mesh | `npm-package-registry` | the forge |
-| `git` | mesh | `git` | the forge |
-| `the-build-machine` | node | — | a builder |
-| `the-dns-port` | node | — | the local resolver |
-| `the-intrusion-prevention` | node | — | an intrusion-prevention service |
-| `the-packet-filter` | node | — | the packet filter |
-| `the-private-network` | node | — | the private network the mesh runs over |
-| `the-resolver-configuration` | node | — | whichever of the alternative resolver configurations is chosen |
-| `the-showcase` | node | — | the showcase module |
-| `the-uplink` | node | — | the program that manages the machine's own network ([ADR 0117](../../02-DECISIONS/0117-a-machines-uplink-is-a-seat.md)) |
+**The set is derived, and only the mesh's half is written here.** Revision, 2026-09-26
+([ADR 0126](../../02-DECISIONS/0126-a-module-declares-its-own-seats.md), superseding
+[ADR 0110](../../02-DECISIONS/0110-a-seat-is-a-module-assignment-from-a-closed-set.md)): a module
+declares its own seats with their protocols, so the seats a mesh has are the mesh's own **plus
+every registered module's**. The set is still closed — a seat named nowhere is refused — but it is
+computed from the catalogue rather than maintained by hand, which is the property 0110 actually
+needed and the table could not keep.
 
-The controller holds this set in code, and a test asserts both its size and that every entry names
-the record that made it a seat. **This table and [ADR 0110](../../02-DECISIONS/0110-a-seat-is-a-module-assignment-from-a-closed-set.md)
-govern, and code that disagrees is what is wrong.** The implementation in progress predates several
+**And the mesh's own half is data, named for its scope.** Revision, 2026-09-27, reconciling two
+records made in parallel: [ADR 0121](../../02-DECISIONS/0121-a-system-seat-is-named-for-its-scope-and-modules-define-their-own.md)
+names a system seat for the scope it is held at — `mesh-*` for one per mesh, `node-*` for one per
+machine — and [ADR 0122](../../02-DECISIONS/0122-a-seat-is-data-a-rename-is-a-database-update.md) moves
+the set out of compiled code into a table the controller owns, so a rename is one write rather than a
+rebuild of everything that names one.
+
+So the set has two halves and neither is written out here: the mesh's own, which the controller holds
+as rows, and every registered module's, which is computed from the catalogue. What this document keeps
+is what a seat *is* — the rest would be a third copy, stale the first time somebody renamed one, which
+is the fault ADR 0122 exists about.
+
+
+**Every seat below is named `mesh-*`, and the prefix is the reservation rule**: a module declaring
+any `mesh-*` name is refused at registration, so there is no reserved-names list to drift. Ten of
+these are renamed to restore [ADR 0079](../../02-DECISIONS/0079-the-foundation-seats-are-named-after-their-servers.md)'s
+convention, which later seats departed from.
+
+| seat | was | scope | delivers | typically held by |
+|---|---|---|---|
+| `mesh-controller` | — | mesh | — | the controller |
+| `mesh-store` | — | mesh | — | the store the mesh's own records live in |
+| `mesh-broker` | — | mesh | `mesh-bus` | the broker carrying the mesh's own bus |
+| `mesh-vault` | — | mesh | `secret`, reserved | the vault |
+| `mesh-artifact-store` | `the-artifact-store` | mesh | `artifact-store` | the artifact registry |
+| `mesh-catalog` | `the-catalogue` | mesh | — | the catalogue |
+| `mesh-npm-package-registry` | `npm-package-registry` | mesh | `npm-package-registry` | the forge |
+| `mesh-git` | `git` | mesh | `git` | the forge |
+| `mesh-build-machine` | `the-build-machine` | node | — | a builder |
+| `mesh-dns-port` | `the-dns-port` | node | — | the local resolver |
+| `mesh-intrusion-prevention` | `the-intrusion-prevention` | node | — | an intrusion-prevention service |
+| `mesh-packet-filter` | `the-packet-filter` | node | — | the packet filter |
+| `mesh-private-network` | `the-private-network` | node | — | the private network the mesh runs over |
+| `mesh-resolver-configuration` | `the-resolver-configuration` | node | — | whichever of the alternative resolver configurations is chosen |
+| `mesh-showcase` | `the-showcase` | node | — | the showcase module |
+
+The controller holds **the mesh's own** entries in code, and a test asserts their size and that
+every one names the record that made it a seat. A module's seats are not here and never will be —
+they are read from the catalogue. **This table and
+[ADR 0126](../../02-DECISIONS/0126-a-module-declares-its-own-seats.md) govern, and code that
+disagrees is what is wrong.** The implementation in progress predates several
 things here: seats held by assignments rather than claimed by definitions, the `mesh-vault` seat and
 its reservation, and the foundation's seats delivering nothing. It is brought to this table before it
 merges.
@@ -121,6 +177,15 @@ moves that to a host port requirement.
 
 ## A seat that delivers nothing
 
+**A module's declared seat may promise nothing too, and that is a marker seat.** Correction of fact,
+2026-09-27: [ADR 0126](../../02-DECISIONS/0126-a-module-declares-its-own-seats.md)'s "a declared seat
+carries a protocol" governs what a *holder* must satisfy, not that every seat offers something. A
+marker seat's protocol is satisfied by holding it, which is the whole of what a marker says. Refusing
+an empty one would refuse most of the node-scoped set, the showcase module's own seat included.
+Nothing reaches that state by accident: an unknown manifest field is refused outright, so an empty
+protocol was written as one. Checked by a registration test accepting a node seat with no protocol
+and by the showcase manifest, which declares one.
+
 Most node seats deliver nothing. They say which module is this machine's packet filter, or which of
 two alternative resolver configurations it runs, and a second holder is refused. That is the whole of
 their job, and it is a real one: it is the mesh saying what a machine is, in words a person can read.
@@ -157,16 +222,24 @@ still to take.
 
 ## How it is checked
 
-The rules here are [ADR 0110](../../02-DECISIONS/0110-a-seat-is-a-module-assignment-from-a-closed-set.md)'s
-and [ADR 0111](../../02-DECISIONS/0111-a-build-source-is-on-the-git-seat-or-external.md)'s, and each is
+The rules here are [ADR 0126](../../02-DECISIONS/0126-a-module-declares-its-own-seats.md)'s —
+which supersedes [ADR 0110](../../02-DECISIONS/0110-a-seat-is-a-module-assignment-from-a-closed-set.md)
+and keeps every rule below except how the set is formed — and
+[ADR 0111](../../02-DECISIONS/0111-a-build-source-is-on-the-git-seat-or-external.md)'s. Each is
 checked as their tables say:
 
 | Rule | Checked by |
 |---|---|
-| The set is closed, and every entry names its decision | 0110: a unit test on the set's size and decisions; manifest tests refusing an unknown seat or the wrong scope. |
-| A seat is held by one assignment, and only by one whose module can hold it | 0110: resolution tests for a second holder and for a seat the definition does not name. |
-| A requirement naming a seat is answered by its holder; a foundation seat cannot be named | 0110: resolution tests with a second provider on the consumer's node, with the seat unheld, and naming `mesh-store`. |
-| Several providers and none local is a person's choice | 0110: an assignment test listing candidates with the seat's holder first and recording the pin. |
-| `secret` is reserved | 0110: the parser and resolution refusals for another provider and a pin. |
-| Holdings are derived, and the overview lists every seat | 0110: the `seats` command test, including an unheld seat. |
+| The set is closed, and every mesh entry names its decision | 0118: a unit test on the mesh's own entries. **The refusal of an unknown seat is at registration, not in the parser** — correction of fact, 2026-09-27: a module may hold a seat *another* module declares, which is the point of naming the seat and not its provider, so whether a claimed name exists is a fact about the whole catalogue and a manifest in isolation cannot be judged on it. Registration tests cover an invented name and a name another module declares; the parser still refuses a claim on the mesh's own `mesh-*`/`node-*` namespace and a scope that disagrees with a declaration in the same manifest. |
+| The set is derived, and enumerating it is a query | 0118: the overview lists the mesh's own plus every registered module's, asserted against a fixture mesh. |
+| `mesh-*` is the mesh's, and a module may not declare one | 0118: a registration test refusing a manifest that declares any `mesh-*` seat, naming the prefix. |
+| Two modules cannot declare the same seat | 0118: a registration test; the second is refused and the first untouched. |
+| A holder satisfies the seat's protocol | 0118: a claim whose module does not serve what the seat declares is refused at assignment. |
+| A seat is held by one assignment, and only by one whose module can hold it | 0118: resolution tests for a second holder and for a seat the definition does not name. 0131: `CanHold` is the one judgement, shared by registration and the handover, and its test follows the store's row. |
+| A holder on record settles the seat; another eligible assignment is silent, not refused | 0131: resolution tests with a recorded holder on the same machine, on another machine, and under a seat's former name; without a record, the old rule's tests still pass unchanged. |
+| A handover replaces the holder as one write, needs an assignment to point at, and goes with it | 0131: store tests — a second handover leaves one row; a handover to a module not assigned where named is refused; unassigning the holder removes the row. |
+| A requirement naming a seat is answered by its holder; a foundation seat cannot be named | 0118: resolution tests with a second provider on the consumer's node, with the seat unheld, and naming `mesh-store`. |
+| Several providers and none local is a person's choice | 0118: an assignment test listing candidates with the seat's holder first and recording the pin. |
+| `secret` is reserved | 0118: the parser and resolution refusals for another provider and a pin. |
+| Holdings are derived, and the overview lists every seat | 0118: the `seats` command test, including an unheld seat. |
 | A build source on the seat records no address; an unheld seat refuses only self-hosted builds | 0111's tests. |

03-DESIGN/01-to-be/27-a-module-requires-the-mesh-resolves.md

@@ -8,7 +8,7 @@ decisions:
   - 02-DECISIONS/0115-one-assignment-of-a-module-per-node.md
   - 02-DECISIONS/0113-the-vault-makes-every-secret.md
   - 02-DECISIONS/0114-a-shared-credential-rotates-over-two-credentials.md
-  - 02-DECISIONS/0110-a-seat-is-a-module-assignment-from-a-closed-set.md
+  - 02-DECISIONS/0126-a-module-declares-its-own-seats.md
   - 02-DECISIONS/0111-a-build-source-is-on-the-git-seat-or-external.md
   - 02-DECISIONS/0084-which-provider-serves-a-consumer.md
   - 02-DECISIONS/0046-a-module-configuration-is-its-assignments-not-its-manifest.md
@@ -64,7 +64,7 @@ Which module answers, in order:
 1. **the holder of the seat the requirement names.** A requirement may name a seat instead of leaving
    the provider open. It asks for *the mesh's* one, and the mesh answers with whichever assignment
    holds that seat, with nothing asked of anyone. Unheld, the requirement is refused, naming the seat
-   ([ADR 0110](../../02-DECISIONS/0110-a-seat-is-a-module-assignment-from-a-closed-set.md),
+   ([ADR 0126](../../02-DECISIONS/0126-a-module-declares-its-own-seats.md) (superseding [ADR 0110](../../02-DECISIONS/0110-a-seat-is-a-module-assignment-from-a-closed-set.md)),
    [26 — The seats](26-the-seats.md)). Only a seat that delivers a provision can be named; naming a
    foundation seat is refused, because it delivers nothing. A `secret` requirement always names
    `mesh-vault`, because that provision is reserved;
@@ -199,7 +199,7 @@ containers, login, broker account and settings are keyed by it, as today, and a
 tightest backend ([ADR 0049](../../02-DECISIONS/0049-a-consumers-identity-fits-the-tightest-backend.md)).
 
 **A module may run on many nodes, and one assignment may hold a seat**
-([ADR 0110](../../02-DECISIONS/0110-a-seat-is-a-module-assignment-from-a-closed-set.md)). The definition
+([ADR 0126](../../02-DECISIONS/0126-a-module-declares-its-own-seats.md) (superseding [ADR 0110](../../02-DECISIONS/0110-a-seat-is-a-module-assignment-from-a-closed-set.md))). The definition
 says which seats the module can hold; the assignment says which it does. So the store module can run
 on every node, one of those assignments holds `mesh-store`, and moving that role changes an
 assignment, not a definition.

03-DESIGN/01-to-be/28-building-the-bus.md

@@ -1,15 +1,21 @@
 ---
 layer: to-be
-status: proposed
-code: []
-updated: 2026-09-26
+status: in-progress
+code:
+  - mesh-catalog modules/nats
+  - mesh-controller internal/catalogue
+  - mesh-lab scenarios
+updated: 2026-09-28
 decisions:
   - 02-DECISIONS/0116-the-bus-is-built-in-five-steps.md
   - 02-DECISIONS/0106-the-bus-is-nats.md
+  - 02-DECISIONS/0131-everything-on-the-mesh-speaks-to-the-broker-seat.md
+  - 02-DECISIONS/0126-a-module-declares-its-own-seats.md
   - 02-DECISIONS/0074-the-wire-is-specified-not-the-types.md
   - 02-DECISIONS/0079-the-foundation-seats-are-named-after-their-servers.md
   - 02-DECISIONS/0100-a-node-in-use-is-adopted-before-it-is-converged.md
   - 02-DECISIONS/0039-what-the-sdk-holds-and-refuses.md
+  - 02-DECISIONS/0130-the-predecessor-is-ending-and-its-broker-goes-with-it.md
 ---
 
 # 28. Building the bus
@@ -111,25 +117,153 @@ step 5  the rollout
 
 ## Step 1 — the module, and genesis raises it
 
+> **Revised 2026-09-26** ([ADR 0126](../../02-DECISIONS/0126-a-module-declares-its-own-seats.md),
+> [design 29](32-what-a-module-declares.md)). Tasks 1.3 and 1.4 said the controller composes every
+> account and creates *the four streams* at genesis, from a fixed set. That is only the mesh's own
+> half. A module declares seats with their protocols, so streams are created **at registration**
+> and durable consumers **at assignment** — neither of which has happened at genesis. The fixed
+> foundation set stays here; the derived machinery moves to step 3, where the declaration model it
+> reads from is specified. Tasks 1.1 and 1.2, already done, are untouched by this: the module and
+> its reload mechanism do not care what the configuration says.
+
 **Why here.** Everything else needs a server to talk to, and genesis is where the foundation is
 defined. The mesh this is for will never travel this path — it is already running, and takes step 2
 — but genesis is the definition every other path is measured against, and one that exists only on
 paper is wrong until there is a second mesh to find out.
 
-- [ ] 1.1 the `nats` module: manifest, image, one container, its client, TLS and monitoring ports,
+- [x] 1.1 the `nats` module: manifest, image, one container, its client, TLS and monitoring ports,
       JetStream on a named volume — the shape of design 25 §5, and the same shape the broker module
       beside it already has
-- [ ] 1.2 the composed configuration as a **directory** resource, and the entrypoint that watches
+- [x] 1.2 the composed configuration as a **directory** resource, and the entrypoint that watches
       the one file and signals the server itself — design 25 §5's correction, kept inside the module
       because a container has no reload and a recreate would drop every connection the mesh has
-- [ ] 1.3 the controller composes that file: accounts, permissions, TLS, JetStream — permissions
-      derived from `emits` and `consumes` and nothing else, plus each user's own ack subject and its
-      own inbox prefix (design 25 §4)
-- [ ] 1.4 the four streams, created at genesis and asserted idempotently on start, by the controller
-      as their only writer
-- [ ] 1.5 genesis raises it as foundation, claiming the seat **`mesh-broker`** — the seat is the
-      server's role, not the product
-- [ ] 1.6 the genesis-broker bed
+- [x] 1.3 the controller composes that file: accounts, permissions, TLS, JetStream — a user's
+      permissions derived from its declaration and nothing else, over the three namespaces of
+      [design 29](32-what-a-module-declares.md) §2, plus its own ack subject and its own inbox
+      prefix (design 25 §4)
+- [x] 1.4 the mesh's own streams, created at genesis and asserted idempotently on start, by the
+      controller as their only writer — **the mesh's own, not all of them**: a seat's streams are
+      created when the module declaring it is registered, and a module's durable consumers when it
+      is assigned, so this task is the fixed foundation set and 3.x carries the derived rest
+- [x] 1.5 genesis raises it as foundation, claiming the seat **`mesh-broker`** — the seat is the
+      server's role, not the product. **Already true of the controller and needed no change**: it
+      resolves the broker by seat ("that is where the broker is, whatever else the topology says")
+      and names no broker module anywhere in its source. What remains is naming `nats` instead of
+      the deprecated broker where a genesis module set is declared, which is scenario and installer
+      configuration — carried with 1.6 rather than before it.
+- [x] 1.7 **the composition, delivered** — the controller gathering its principals, composing the
+      file, and asserting the streams and consumers on start.
+
+      **In**: the user list is derived from the mesh's records and the credentials are kept.
+
+      A bus user's bcrypt hash is now recorded, keyed by the username the file needs, and the
+      plaintext is returned exactly once. That state is new and the reason is worth stating: on the
+      bus the mesh runs on today an account is a management call — mint, hand over, seal to the
+      holder, keep nothing — and that works because the broker remembers. Here the users are one
+      file rewritten whenever any of it changes, so keeping nothing would mean **the first person's
+      access change silently blanking every module's password**.
+
+      **Permissions are not kept, only credentials.** Authority is derived from what each module
+      declares every time the file is written ([ADR 0043](../../02-DECISIONS/0043-a-module-broker-account-is-scoped-by-emits-and-consumes.md));
+      a stored permission list would be a second account of a user's authority, able to disagree
+      with the records it came from while both looked internally consistent.
+
+      The derivation refuses two things where they can still be named: two users with one name — the
+      server reads the file as one of them and which one depends on the order — and a module
+      assigned but absent from the catalogue, which would compose a user with no authority and fail
+      on its first publish with an authorisation error that says nothing about a missing manifest.
+      A user the mesh has minted no password for is *named* rather than dropped or written as a user
+      anybody is: an ordinary situation with an obvious remedy, and the caller decides whether a
+      partial file is worth writing. A seat's protocol is gathered across the whole catalogue, not
+      from one manifest, because a seat is declared by one module and held by another.
+
+      **Out, and what each needs.**
+
+      **Delivery is in, and it settled what a module declares.** The mesh writes the *accounts* and
+      the module owns its *server*. The alternative was a manifest field enumerating ports, TLS
+      paths and a store directory so the controller could write a whole configuration — wrong,
+      because those are properties of the container the module raises and the controller would have
+      to be kept in step with a Dockerfile it never sees. So a module declares its own configuration
+      as a file resource and `bus-users` names where the mesh's half goes beside it; **asking is not
+      enough to receive it**, because that file holds every user's password hash, so the claim on
+      `mesh-broker` is what authorises it.
+
+      Two things a running server changed. **An absolute include path is resolved relative to the
+      including file's directory** — `include /etc/nats/accounts.conf` from another directory makes
+      the server look for it *under* that directory and refuse to start — so both files share one.
+      And **`verify: true` was refusing every connection in the mesh**: it makes the server demand a
+      *client* certificate, and nothing in the mesh presents one — a host pins this server's exact
+      certificate and authenticates with the password the mesh minted ([ADR 0004](../../02-DECISIONS/0004-a-node-and-how-it-joins.md),
+      design 25 §4). Every connection would have died at the TLS handshake before any password was
+      looked at, with an error that reads as a fault in the client. Removed; TLS is still required,
+      because the block is what requires it and `verify` only decides whether client certificates
+      are checked. **Design 25 §4 should say this**, and says nothing about it today.
+
+      Also collected here: task 1.2's payoff, end to end against the module's own image — the user
+      list rewritten, the module noticing and reloading the server itself with no signal from
+      outside, and the connection the mesh already had still working afterwards.
+
+      **Minting is in, on both halves.** A node at enrolment, a module when its credential is
+      issued. Three things differ from a management call and each is the point of the move: the
+      credential is minted into the mesh's records and becomes usable at the next composition, so no
+      server need be reachable for it; the password travels beside the address rather than inside it,
+      because a credential embedded in a URL leaks into every log line that prints a connection; and
+      a module's durable consumer is derived from what it declared rather than named, so it cannot ask
+      for delivery of something it did not say it consumes. A node reconnecting may be refused until
+      the composition reaches the machine running the bus — which is what the host's reconnect backoff
+      is for, where waiting for the push would hold an enrolment open for as long as a declaration
+      takes to apply.
+
+      **Which bus is one fact, and being told about both is refused at start.** Not warned about: a
+      mesh half on each is one where a declaration goes out on one bus and the report comes back on
+      the other, and every component logs success while it happens — ADR 0074's failure arriving
+      through configuration instead of through code. A node that came away holding a credential for
+      each could be half-moved, and nothing would say which half.
+
+      **The objects are asserted on every start**, not created once at genesis: a stream somebody
+      deleted, a mesh raised from a restored backup, or a bus whose data directory was replaced all
+      have records and no objects, and a node whose consumer is missing hears nothing while everything
+      else about it looks correct. Against a real server: every object accepted, asserting twice
+      changes nothing (a start that failed the second time is a controller that cannot restart), a
+      machine joining an already-raised bus accepted, each node's consumer bound to its own
+      declaration subject and no other's, and CONTROL not dead-lettering — because the store window's
+      bound is the controller's, and a server that gave up first would discard the push the stream
+      exists to protect.
+
+      **People are not in the list**, deliberately: the account model is built and `operator issue`
+      is not (4.4), so there is nobody to derive. Left empty rather than guessed at.
+
+      > **This corrects a tick, not a decision.** Tasks 1.3 and 1.4 are ticked and they are honest
+      > about what they built — the composer, the derivation, the permission model, the stream and
+      > consumer definitions, the asserter, all pure and held by unit tests and a golden
+      > composition. What nobody wrote is the *caller*. Measured on the feature branch: outside the
+      > package that defines them, there is **not one** use of the composer, the permission
+      > derivation, the stream set, the stream asserter or the principal type. Step 1's "done when"
+      > claims "every account and permission composed from the manifests", and a mesh raised today
+      > would stand up a server with no user list at all.
+      >
+      > It also needs state the mesh does not keep. Design 25 §4 says the file holds bcrypt
+      > hashes, and passwords are "minted and sealed exactly as today" — but today the mesh mints a
+      > password, hands it to the broker through a management call, seals the plaintext to the
+      > holder and **keeps nothing**. There is no management call here, so the hash has to survive
+      > for every later recomposition: the first thing a person's access change or a new module
+      > touches is a file that must still contain every other user's password. No bcrypt hash is
+      > stored anywhere in the controller today.
+      >
+      > Named as its own task rather than folded into 1.3 so the gap is visible: the parts of
+      > step 1 exist and the mesh does not yet do any of it.
+
+- [ ] 1.6 the genesis-broker bed — **deferred**: beds are run once, at the end, rather than per
+      step (novox/hq design 22's rule, and the operator's instruction). Every claim step 1 makes
+      is covered by a unit test or was demonstrated against the real server; what the bed adds is
+      the claims that need a mesh.
+
+> **Not done here, deliberately.** The controller builds a module's broker credential as an
+> `amqps://` URL and defaults a portless genesis address to 5671. Those are correct until the
+> rollout and must not move: steps 1 to 4 leave every node on AMQP
+> ([ADR 0116](../../02-DECISIONS/0116-the-bus-is-built-in-five-steps.md)), so changing the
+> credential's shape now would break the running bus to serve a bus nothing speaks yet. They
+> change with the links, in step 3.
 
 **Done when.** A mesh raised from nothing has the server standing with the streams asserted and
 every account and permission composed from the manifests; a user cannot publish outside its
@@ -149,11 +283,35 @@ and it is what makes steps 3 and 4 safe to develop against a live mesh. A runnin
 a foundation module by being raised again; it adopts one in place
 ([ADR 0100](../../02-DECISIONS/0100-a-node-in-use-is-adopted-before-it-is-converged.md)).
 
-- [ ] 2.1 the server raised beside the existing broker on its own ports, carrying nothing
-- [ ] 2.2 the `nats` module adopted onto it in place, holding the data and configuration it was
-      raised with
-- [ ] 2.3 the seat claim, and the resolver's refusal of a second holder mesh-wide
-- [ ] 2.4 the adoption bed
+- [ ] 2.1 the server raised beside the existing broker on its own ports, carrying nothing —
+      installer-side, from the upstream image
+- [ ] 2.2 the `nats` module assigned, which **recreates the container once, deliberately** (see
+      below), keeping its JetStream directory
+- [x] 2.3 the seat claim, and the resolver's refusal of a second holder mesh-wide — **already
+      true and now proved**: the refusal is generic to any mesh-scoped seat, and three tests pin
+      what matters for this one — a second bus anywhere is refused naming the seat, a *different*
+      bus implementation is refused for the same reason (which is what lets the bus be replaced
+      at all), and the deprecated broker no longer contends for it, so both run on one mesh
+- [ ] 2.4 the adoption bed — deferred with the other beds
+
+> **Adoption here is not a no-op, and pretending it would be is the trap.** The host keeps an
+> existing container only when its spec matches the declaration exactly
+> ([`apply.go`](https://git.novox.be/novox/mesh-host): *existed && before.Spec == want && running*
+> → unchanged; anything else is `rm -f` and recreate). Genesis raises the server from the
+> **upstream** image, because nothing has been built yet; the module declares the **mesh-built**
+> artifact, which carries the entrypoint that reloads configuration in place. Those two specs
+> differ, so assigning the module recreates the container.
+>
+> That is correct, and it is [ADR 0067](../../02-DECISIONS/0067-genesis-is-a-pivot.md)'s pivot
+> exactly: raise a temporary thing, then reinstall it as an ordinary module. It is safe **only
+> because it happens while the bus carries nothing** — which is what 2.1 means by "carrying
+> nothing", and why step 2 comes before anything speaks NATS rather than after. One recreate, at
+> the one moment it costs nothing.
+>
+> **After that, never again.** The configuration is a directory mount rather than a file, so
+> rewriting accounts does not change the container's spec and the entrypoint reloads the server in
+> place. That is the whole point of task 1.2, and this is the moment it pays: every later account,
+> permission or person's access change touches a running bus with connections on it.
 
 **Done when.** A mesh already running has the server adopted, holding `mesh-broker`; a second
 assignment anywhere is refused at resolution — *one per mesh*; and every node is still on the old
@@ -166,19 +324,160 @@ quietly carried traffic would be step 5 arriving early and unrehearsed.
 that decides what "agreeing" means for everything after it. It is the largest step and the one that
 pays for itself furthest away.
 
-- [ ] 3.1 **the suite first, on the bus the mesh has** — fixtures for the envelope and its required
-      headers, the contributions file, a served tool call and a grant, capturing what the three
-      implementations do *today*. Written first because a suite born on the new bus certifies
-      whatever the new bus happens to do
-- [ ] 3.2 design 19 rewritten from exchanges, queues and routing keys to the subjects and streams of
+- [x] 3.1/3.3 **the fixtures** — one directory in the sdk, read by each implementation's own
+      runner rather than copied into either, because a fixture copied twice is two fixtures. The
+      Go emitter and the runtime's NATS client both pass the first: every required header set,
+      each value in the pinned shape, the subject derived the same way, and the payload the body
+      alone.
+
+      **The suite also had to settle what "byte-for-byte" can mean**, which ADR 0074 stated and
+      nothing had yet had to implement. The envelope is exact — subject, required headers, names
+      and formats — because that is what two implementations get wrong invisibly. The body is
+      not: Go sorts a map's keys and JavaScript keeps insertion order, so identical bytes would
+      commit every implementation to a canonical JSON encoder, to buy a property the mesh never
+      uses. Read strictly it would have sent somebody writing one.
+
+      Still to capture: a served tool call, a grant and its answer, and the contributions file —
+      the other three ADR 0074 names.
+- [x] 3.2 design 19 rewritten from exchanges, queues and routing keys to the subjects and streams of
       design 25 §2–§3, per capability, with ADR 0074's model untouched: floor plus capabilities, an
       implementation legitimate when it claims less, identity from the sealed credential, dedup on
-      `x-event-id`
-- [ ] 3.3 the fixtures restated on NATS, and the capability each implementation claims
-- [ ] 3.4 the controller's link on NATS
-- [ ] 3.5 the host's link on NATS — mirroring, still importing nothing
-- [ ] 3.6 the tool runtime's client on NATS, behind the unchanged sdk contract
-- [ ] 3.7 the sdk's three stale comments, and nothing else in it
+      `x-event-id`. Claims checked against a running server are marked *verified* in the text, so
+      a reader can tell what was measured from what was reasoned. One limitation lifts with the
+      transport: a module may now call another's tool, which issue 049 recorded it could not.
+- [x] 3.4 the controller's link on NATS — **both halves are through the seam, and the store
+      window is the server's.** `Bus` states the outbound in the mesh's words (publish an event,
+      declare to a node) and `Control` states the inbound (took it, dropped it, held it for the
+      store); each has an AMQP and a NATS implementation, and both ship, because steps 1 to 4
+      leave every node on AMQP and both shipping is what holds them to one envelope.
+
+      The outbound seam turned out to be eight call sites; the inbound was the larger half, and
+      the reason: every handler took the transport's own delivery type, so the loop could not move
+      without moving enrolment, reports, builds, upgrades and catch-up with it in one breath.
+
+      **The window (ADR 0083) is now what decides, once, for both.** On the bus the mesh has,
+      holding a message means an unacknowledged delivery kept in the controller, bounded by the
+      prefetch and lost if it stops. On the bus being built it is a `nak` with a delay: the
+      message stays the server's and the controller keeps only the moment it first could not take
+      it, so one that restarts mid-window has nothing to lose. Seven claims about that were asked
+      of a running server rather than reasoned — a report heard and gone from the work queue, one
+      held through a store outage and recorded when it returned, one let go once the bound passed,
+      a superseded one settled without being acted on, a heartbeat heard and nothing persisted,
+      both followed events acknowledged on a stream the controller had no ack subject for, and the
+      enrolment answer arriving at the address the request carried in its payload.
+
+      **Three things the wiring forced into the open.**
+
+      *Supersession is asked before the store, not after.* A report about a declaration the mesh
+      has moved past would otherwise wait out a restarting store to be written, and then overwrite
+      what the node is doing now.
+
+      *Half of a report is not about a declaration, and that half is never stale.* What the machine
+      **is** — the tunnel it took over, the ports its own bundle holds, what an adopted node found,
+      a node moving its overlay key — reaches the mesh on a report and nowhere else. A rekey set
+      aside as stale is a node whose overlay key never moves, and no retry is coming, because the
+      node said it once. So staleness is asked only of a report that is purely an apply's account.
+
+      *The controller could not have consumed a module event at all.* Its account granted no event
+      subject to subscribe and no ack subject on the events stream, so every announcement would
+      have been redelivered for ever, refused by the permission list it already had. Both are now
+      granted, each subject named rather than by pattern — a controller subscribing every event in
+      the mesh is a permission list that has stopped saying what it is for. Its consumers are
+      **named beside the mesh's own streams rather than derived**, because the controller files no
+      manifest and authority cannot come from a declaration that does not exist.
+
+      Still outstanding: a build's own shape, which travels with the builder in step 4.
+- [x] 3.5 the host's link on NATS — **all three halves are through seams**, mirroring the
+      controller's and still importing nothing of the mesh's own (ADR 0005): the host's own
+      interfaces over its own libraries, agreeing with the controller only because a fixture holds
+      both to one envelope. A report goes through JetStream because it is the message the
+      store-window guarantee is about; a heartbeat stays on core, because a heartbeat in a stream is
+      the mesh's least valuable message competing for retention with its most valuable.
+
+      `Link` is dialling, hearing and saying in one interface, because **dialling is where the
+      transport is chosen** and choosing it twice is how one half of a node ends up on a different
+      bus from the other. `Asking` is the enrolment conversation, and it is separate for the
+      opposite reason: almost nothing about it is the same, and a node that fails there is not in
+      the mesh at all.
+
+      **What the new bus took away, and what it would not give.** A host declares nothing here: on
+      the old bus it declares its own queue, because a queue that is not there means a node that
+      hears nothing, but the object it reads through now is a durable consumer and a host's account
+      reaches no part of the JetStream API. So it **binds** to one the mesh made, and a missing one
+      is said as the mesh's to answer rather than quietly created with whatever the client defaults
+      to. Two things that had to be built for that: a node's declaration consumer (named after the
+      node, because its ack grant is derived from the node's name, so any other name is a delivery
+      it cannot acknowledge), and the enrolment user's **inbox** — design 25 §6 names it and the
+      composer granted none, so an enrolling node would have published its request and waited out
+      its timeout against a mesh that answered.
+
+      **The reply address travels in the payload, and that is now proved from both ends.** The
+      controller reads it from there (3.4) and the host writes it there and waits on it, and the
+      test asserts the transport's own reply field held the *consumer's ack address* by the time the
+      request arrived — so a future server that stopped claiming that field fails a test rather than
+      letting the reason quietly become folklore.
+
+      The host's **"newest wins" window narrows at the rollout rather than disappearing**, and that
+      is now measured rather than predicted: three declarations pushed to an absent node leave one
+      on the stream and it is the newest, so the catch-up half is the stream's — but three pushes to
+      a connected node are still three deliveries, which is the half that stays.
+
+      **The pin turned out easier here than in the tool runtime, not harder.** The Go client takes a
+      `*tls.Config`, so the same pinned configuration with the same verify callback does the work;
+      the subject-alternative-name constraint recorded under 3.6 is that client's, because it takes
+      PEM strings with no verify hook. A host checks the fingerprint and nothing else.
+
+      Nothing here composes an enrolment user per live token, and that is **1.7's**, not this
+      task's: it is one input to a composition that does not happen at all yet.
+- [x] 3.6 the tool runtime's client on NATS, behind the unchanged sdk contract — round-tripped
+      against a real server: a tool answered across two connections, a throwing handler reaching
+      the caller as an error rather than a timeout, an event delivered once with its key, body,
+      node and event id intact. Ships beside the AMQP client and is selected at the rollout,
+      because steps 1 to 4 leave every node on AMQP.
+
+      **A constraint it surfaced, recorded where somebody issuing a certificate will look.** The
+      AMQP client pinned the exact certificate and switched hostname verification off, which is
+      sound because a fingerprint is stronger than a name. The NATS client exposes no equivalent
+      hook — its TLS options are PEM strings with no verify callback — so the pin still happens
+      before dialling and the library's own name check happens beside it. **The bus's certificate
+      must carry a subject-alternative name matching the address nodes dial it by**, or the
+      connection is refused by a library error rather than by anything the mesh says.
+- [x] 3.7 the sdk's three stale comments, and nothing else in it — three lines, which is the
+      whole of the sdk's diff for the bus change, and the measurement that predicted it
+- [x] 3.8 **the declaration model** of [design 29](32-what-a-module-declares.md): local names
+      derived to subjects, the three namespaces, permissions computed from a declaration, and a
+      manifest that contains no subject. Done in the controller's composer (permissions, streams,
+      consumers), in the runtime's client (subjects derived from the credential, never named by a
+      module), and as a catalogue test asserting all 72 manifests hold no subject — because the
+      rule held by construction, and a rule held by construction is one a later field breaks
+      quietly.
+- [x] 3.9 **seats declared by modules** — the manifest now carries `seats` (name, scope,
+      accepts/emits/serves, retention) and `uses`, and registration refuses a `mesh-*` name, a
+      duplicate declarer, an undeclared `uses` or claim, a seat with no protocol, a scope
+      mismatch, and a holder that does not answer what its seat promises. **Still to do**:
+      creating a seat's streams at registration and its holder's work-queue consumer at
+      assignment, which need the JetStream client wired in.
+
+      The refusal for an unknown claim *moved* rather than disappeared — the parser cannot judge
+      it from one manifest any more, because another module may legitimately declare that seat,
+      so it is registration's. The test that encoded the old rule was rewritten rather than
+      deleted, and a second one pins the case the parser could not distinguish.
+
+      **Done**: a seat's work queue is derived and created, and a holder's worker with it. The
+      JetStream client behind them is wired and verified against a running server, which also
+      completes 1.4's missing half — the pure `Asserter` had no implementation until now.
+- [x] 3.10 **the ten seat renames** — done in the controller's table, the ten manifests that
+      claim them, the controller's own shipped manifests, and every test. Not a migration after
+      all: a holding is derived at resolution, never stored, so nothing recorded points at an old
+      name (recorded as a progressive insight on ADR 0126). A **kept** rename table tells a
+      manifest written against an old name what it became, because a module lives in its own
+      repository and may be registered long after the catalogue stopped using one.
+
+      **A seat and the interface it delivers are different names.** The `git` seat became
+      `mesh-git` while the `git` *provision* it delivers did not change, and the same for the
+      package registry. A blanket replace got this wrong first and the failure read "the package
+      registry is served on `<nil>`", which does not say "you renamed an interface" — so a test
+      now pins every seat against the interface it delivers.
 
 **Done when.** The fixtures are produced and consumed byte for byte by every implementation that
 claims the capability, and a module built before any of this serves its tools unchanged on the new
@@ -196,6 +495,17 @@ module.
 **Why here.** The links exist from step 3, so the flows that are not on the bus at all can move onto
 it, and the beds that need a mesh living on NATS can finally run.
 
+> **A blocker surfaced here that is not this step's to fix.** Every event name in the catalogue is
+> still written the way a routing key on the bus the mesh has is written, so the derivation design 29
+> §1 specifies turns a consumer's declaration into a subject **no emitter publishes** — thirty-seven
+> manifests, and one that cannot be composed at all. Nothing fails on the bus the mesh runs on
+> today, where a routing key is matched literally; it fails on the first mesh raised on the new bus
+> and not before, which is why wiring the controller's own subscription is what found it. Opened as
+> [issue 127](../../04-ISSUES/127-a-module-event-derives-a-subject-nothing-publishes/00-report.md).
+> It holds 4.2, 4.3 and the catch-up half of 4.5; the node-facing flows — enrolment, reports,
+> heartbeats, a build's outcome — are unaffected, because those subjects are the mesh's own and
+> derive from nothing a module declares.
+
 - [ ] 4.1 **the full genesis bed** — a mesh raised on NATS from nothing and living on it: a node
       enrols over TLS with a claimed token and the enrolment user cannot read a declaration; a push
       is held while the store restarts and applies after, nothing lost or duplicated; a node that
@@ -204,13 +514,111 @@ it, and the beds that need a mesh living on NATS can finally run.
       held by a `nak`-with-delay cycle still reaches the enrolling node, proving the reply travels
       in the payload and not the transport field the consumer's ack has claimed. The server-enforced
       permissions were proved at step 1 and are not re-proved here
-- [ ] 4.2 a build source's change reaches the builder over the bus, and the build that follows is
-      the one the change asked for
-- [ ] 4.3 an installation completes over the bus, with the same outcome as the path it replaces
-- [ ] 4.4 a person's client: the account, the client that speaks the bus, and the tool surface over
-      it (design 25 §7) — a module's tool invoked from another node and from a person, refused from
-      an account that may not
-- [ ] 4.5 reports and catch-up: a node that was unreachable catches up rather than losing them
+      — **nothing is outstanding but the bed itself.** Both links speak NATS, the composition
+      happens, and every claim above has a unit test or a check against a running server behind it.
+      What none of them can stand in for is a mesh raising itself, which is what this bed is — so this
+      is where the code stops and the lab starts
+- [x] 4.2 a build source's change reaches the builder over the bus, and the build that follows is
+      the one the change asked for — **a build is work submitted to a role now**
+      ([ADR 0129](../../02-DECISIONS/0129-a-seat-carries-the-protocol-of-its-role.md)). Both sides
+      are behind a seam with an implementation per bus, and on the bus being built one publish does
+      what two did: the outcome is the role's own event, so the asker matches it by the id its
+      request carried, the controller records it and the catalogue places it in the graph. A build
+      machine needs a reply queue for nothing and a grant over nobody's inbox.
+
+      Checked against a running server: the round trip; a third party on the role's event hearing
+      the same outcome the asker did, which is what the decision rests on; work leaving the queue
+      once settled, so no second machine repeats it; work submitted with no machine holding the role
+      **waiting rather than failing**, and being done when one arrives; and work a machine handed
+      back coming round again.
+
+      The outcome carries the module name, because only the manifest says what was built and one
+      message now has three readers. A failed build names none: it produced no module version, and
+      the catalogue would otherwise place something that was never made.
+- [x] 4.3 an installation completes over the bus, with the same outcome as the path it replaces —
+      **the installer can raise it**: a foundation template that stands up the server, writes the
+      server's own settings and the mesh's first user list beside them, and starts a controller
+      reaching the new bus. What remains is running it, which is 4.1's bed.
+
+      **The mesh composes its own user list, and at genesis there is no mesh to compose one.** So the
+      installer carries the first — the controller's account at a well-known bootstrap password,
+      exactly as the store is reached at `postgres:bootstrap` and the old bus at `guest:guest`, and
+      rotated with them. From the controller's first composition onward the file is the controller's.
+
+      That surfaced a gap reading would not have found: the controller's own account exists before
+      there is a controller to mint one, so nothing recorded a hash for it and its first composition
+      would have left the writer out of the file it was writing — a bus nothing can connect to,
+      produced by the thing connected to it. It records a hash of the credential it is using, and only
+      when none is recorded, so a restart cannot put the bootstrap password back over a rotated one.
+
+      **The carried list and the derived one are checked against each other**, because they are two
+      statements of one fact and a mesh cannot be raised twice to find out they disagreed. A template
+      granting less than the controller derives produces a mesh that comes up, connects, and is
+      refused on its first act, with an authorisation error naming a subject rather than the template
+      that forgot it. The check earned itself at once: the composer was granting a role's whole event
+      branch *and* the one event it follows, and the wider grant wins — so only the submitting half of
+      a role is granted now, and what comes back is named exactly.
+- [x] 4.4 a person's client — **the account and the program are both in.**
+
+      **The account**: a person is not a module and holds no seat, so their authority is a list of
+      tools (or `*` for an administrator) and nothing else. Held to four properties, each a way of
+      being wrong that would not announce itself: nothing but tools, so a person cannot claim a
+      module said something; no ack subject, because authority over a consumer that does not exist
+      is authority nobody audits; no ability to answer, because a person who can answer a request is
+      impersonating a module on a bus where anyone may serve a tool; and two people do not share an
+      inbox. Issued, listed and revoked by command; stating what somebody may call replaces what was
+      there, because a list that could only grow is a permission nobody can take back; and forgetting
+      somebody takes their credential with them, or it is not a revocation.
+
+      **The program**: two surfaces over one thing — a command line and an MCP server — both adapters
+      over the same three calls, because a second way of reaching a tool is a second thing to keep
+      correct. It uses the client a module's runtime uses, so what a person may do is answered by the
+      same permission list that answers it for a module and an audit has nothing separate to read.
+
+      Three decisions in it worth keeping. It lists what the **catalogue** has rather than what this
+      credential may call: somebody seeing only their own tools cannot tell "not installed" from "not
+      yours", and those need different people to fix them. A failed call says which of three things
+      happened — nobody serves it, this credential may not, or the tool was slow — because the
+      remedies are in three different places and without that they are one timeout and a stack trace.
+      And the MCP surface decides nothing: the names are the ones a person types, the schemas are the
+      modules' own, an answer is passed through unshaped, and a tool that fails comes back as a tool
+      error rather than a protocol error, because the request was well-formed and the mesh answered it.
+
+      Both surfaces are driven against a running bus, including a host's notification being answered
+      with nothing and an unknown method refused.
+
+      > **Design 25 §7 says "nothing is built of this before §10's bed passes", and this was built
+      > before.** Recorded rather than quietly ignored: the operator asked for it, it is on the
+      > critical path for nothing and blocked by nothing, and the bed it waits for is 4.1's. If the
+      > bed changes what a person's client should be, this is what gets changed.
+
+- [x] 4.5 reports and catch-up: a node that was unreachable catches up rather than losing them.
+
+      **The reports half is in and proved against a server** (3.4): held through the store's absence by
+      the server rather than by the controller, superseded ones settled by the digest they carry.
+
+      **The catch-up half needed nothing built, and that was the answer.** It existed because a queue on
+      the bus the mesh runs on today receives only what is published after it is bound, so everything
+      built before the catalogue existed was announced to nobody — and on a fresh mesh that is always
+      the foundation, because those are the things the catalogue needed in order to exist
+      ([issue 050](../../04-ISSUES/050-the-catalogue-knows-nothing-built-before-it/00-report.md)). A
+      whole mechanism followed: the catalogue asks, the controller re-publishes.
+
+      A stream is a log and a consumer is a position in it. A consumer created later starts at the
+      beginning, so the builds are simply there — asked of a running server rather than assumed, since
+      the decision rested on it: three builds published with nothing listening, then a consumer created,
+      and all three waiting for it. So the question of *who replays* has no answer because nothing
+      replays.
+
+      > **This is the shape of the whole change, in one task.** Three ways to do the replay were weighed
+      > — a namespace for the mesh's own voice, the controller answering a question, a consumer reading
+      > from the start — and the right answer was that the bus being moved to already does it. The
+      > mechanism was never about builds; it was about a queue that could not remember. **A conversion
+      > that carried it across would have carried a workaround for a limitation that no longer exists**,
+      > and nothing would have looked wrong.
+
+      Retiring it is step 5's, with the rest of what only the old bus needs: the request, the
+      re-publishing, and the `replay` flag that told a consumer to register history without acting on it.
 
 **Done when.** Each converted flow is proved against the behaviour it replaced, and the full genesis
 bed is green. **Observation is not in this step** — heartbeats, conditions and key-value state are
@@ -221,16 +629,101 @@ reserves them for after the move, and a flow built ahead of its design would be
 
 **Why here.** It is the only step that moves a node's bus, and it moves every node's at once.
 
-- [ ] 5.1 the cutover bed: a mesh on AMQP with a predecessor stand-in on the compatibility broker
+**The order the repositories land in is part of the rollout, not paperwork.** Derived 2026-09-27
+while merging, and not obvious from any one repository, which is why it is written here rather than
+left to be re-derived under time pressure:
+
+| order | repository | why it cannot be later |
+|---|---|---|
+| 1 | this one | prose; nothing deploys |
+| 2 | the sdk | comments only, and no module rebuilds for it |
+| 3 | the client library | it is what a module calls to emit, and it is where the subject is derived. Until it lands, a locally-named event is published under the local name itself |
+| 4 | the catalogue | every manifest and every module's code, renamed together. Safe only once the runtime derives |
+| 5 | the controller | **it refuses an old-style event name outright**, so landing it before the catalogue makes every unconverted module unregisterable |
+| 6 | the hosts | last, because nothing else waits on them |
+
+Two properties make the sequence safe rather than merely ordered, and both are pinned by tests. A
+name already in the old form passes through the derivation untouched, so a module nobody has
+converted keeps working at every step. And a converted name derives to **exactly** the key the old
+bus published, so steps 3 and 4 change nothing on the wire — the move to the new bus is step 5.2 and
+one environment variable, not a side effect of deploying.
+
+The failure this ordering avoids is issue 127's own: a publisher and a subscriber that disagree about
+a subject produce no error anywhere. Nothing logs, nothing retries, and the mesh reports itself
+healthy while reacting to nothing.
+
+- [ ] 5.1 the cutover bed: a mesh on AMQP with a predecessor stand-in on the deprecated broker
       moves its bus in one rollout, every node reporting on NATS afterwards, the stand-in's own
       client still connected throughout
-- [ ] 5.2 the rollout: accounts composed, then the controller, every host and every runtime
-      together; every node confirmed heard before AMQP stops
-- [ ] 5.3 the mesh's accounts removed from the compatibility broker, leaving the predecessor's users
-- [ ] 5.4 the compatibility broker retires when its condition holds — no client connected for the
-      period the operator sets
+- [x] 5.2 the rollout: accounts composed, then the controller, every host and every runtime
+      together; every node confirmed heard before AMQP stops.
 
-**Done when.** Every node reports on NATS and the predecessor's clients never noticed.
+      **Done 2026-09-28, 02:25.** Every machine reports on the new bus, the seat is held by the
+      module that provides it, the old broker is unassigned and forgotten, and every credential was
+      minted afresh at the end because two had been printed on the way. What it took, in the order
+      it was found, each fixed on the trunk before the next step: the control plane's `serve` and
+      `push` never selected the new transport (task 4.3, open until then); a machine's user was
+      granted neither the asking nor the delivery of its own consumer; the account had no JetStream
+      of its own; the control plane's client verified the bus's certificate by name instead of
+      pinning it; the seat table's rows carried no protocol, so no role's work queue was raised; the
+      build machine decided its bus from a variable its container never received; and a rotation
+      put new hashes on the bus before three machines had received their new memberships — which
+      is why there is now `rollout hand <node>` and a host adopts a delivered membership at start.
+      The bootstrap loop — a bus that can only be raised by a declaration that can only arrive
+      over that bus — was broken once, by hand: the mesh's own composed configuration started the
+      server, and the controller binary was run on the node directly until the managed container
+      could be rebuilt over the bus it was on.
+
+- [x] 5.3 **the seat changes hands as one act.** A command takes a seat and the assignment taking it
+      over, and the seat is never empty in between — the emptiness is the outage of 2026-09-27, when
+      the control plane, which finds its own bus through this seat, lost the address and looped.
+      **Built 2026-09-27** (`seat_holding`, migration 0039; design 26 says how it is checked), and used
+      live the next night to hand `mesh-broker` from the old broker's assignment to the new one's. This
+      is what 5.2 uses to move `mesh-broker` from the old
+      broker's assignment to the new one's, and it is built first ([ADR 0131](../../02-DECISIONS/0131-everything-on-the-mesh-speaks-to-the-broker-seat.md)).
+- [x] 5.4 **the old broker and everything that named AMQP leave the mesh** ([ADR 0131](../../02-DECISIONS/0131-everything-on-the-mesh-speaks-to-the-broker-seat.md),
+      superseding [ADR 0127](../../02-DECISIONS/0127-amqp-is-a-provision-not-the-bus.md)): the two modules that
+      required `amqp` are removed, the broker's module is unassigned and removed (**done 2026-09-28**; the predecessor's own tooling, which rode the same adopted broker, went dark with it, as [ADR 0130](../../02-DECISIONS/0130-the-predecessor-is-ending-and-its-broker-goes-with-it.md) accepted), registration refuses
+      a manifest that provides or requires `amqp`, and a whole-catalogue check asserts none does. Not
+      a retirement condition — a decision, taken, with the operator's "I don't care if the predecessor
+      breaks" on record ([ADR 0130](../../02-DECISIONS/0130-the-predecessor-is-ending-and-its-broker-goes-with-it.md)).
+      Retiring with it: the build outcome's second announcement under the module's own name, which
+      existed only so a catalogue deployed before the rename and one after both heard it.
+
+      > **The remote tooling goes with it too.** The predecessor's own mesh talks over that broker, so
+      > shutting it down ends the path that reaches this installation's machines from a workstation.
+      > The rollout is driven from the node, or before the broker stops — a sequencing constraint on
+      > 5.2, not an afterthought.
+- [x] 5.5 **the AMQP transport is deleted from the control plane and the hosts**. One bus, nothing
+      to select ([ADR 0131](../../02-DECISIONS/0131-everything-on-the-mesh-speaks-to-the-broker-seat.md)).
+
+      **Done 2026-09-28.** The control plane's old consume loop, build request, tool call, management
+      API and account scoping went, and the host's old dialling and enrolment paths with them; a
+      membership or token naming any other bus is refused before anything is sent. Nothing selects a
+      transport any more: the variable that once did (`MESH_BUS_NATS`) now only names where the
+      control plane reads its own bus credential, the way any module reads a secret. **Checked by the
+      build**: neither repository's module file names the AMQP client library, so a line that still
+      used it would not compile. The store-window guarantee ([issue 083](../../04-ISSUES/083-other-control-messages-are-lost-while-the-store-restarts/00-report.md))
+      is tested against a bus-less fake rather than the old transport's memory, which is what let
+      that memory go — the one thing it did that the stream does not (superseding a held report) is
+      the staleness check on the message itself (design 25 §3).
+
+      Found on the way: **no build had ever recorded what it stood on.** A recipe reads its base from
+      a build argument, so the digest was never in the file the builder derived edges from, and every
+      order that says *bases first* — `build --on`, `build --behind`, the merge follow-up of
+      [issue 131](../../04-ISSUES/131-nothing-tells-the-mesh-a-source-moved/00-report.md) — walked a
+      graph with no edges. The builder now reports the bases it was handed, the control plane records
+      them by artifact path, and the graph is read from the newest build of each module — a recorded
+      manifest carries no `build.on`, so the edge is derived from the build or it does not exist.
+
+> **The old 5.4 note is history.** It recorded that a retirement *condition* was wrong from
+> [ADR 0127](../../02-DECISIONS/0127-amqp-is-a-provision-not-the-bus.md) onward, which framed the old broker
+> as an ordinary provider with no end. [ADR 0131](../../02-DECISIONS/0131-everything-on-the-mesh-speaks-to-the-broker-seat.md) ends that
+> framing in turn: the broker is not kept as a provider either, because AMQP is not a provision. Both
+> readings are kept here so the two reversals can be read in order.
+
+**Done when.** Every node reports on NATS, and nothing of the mesh's own is left connected to the
+deprecated broker.
 
 ## The through-line
 
@@ -245,8 +738,10 @@ itself moves once, at the end, on one day.
 - **Observation** — research 017's, after the move, by its own design.
 - **Leaf nodes** — design 25 §11 keeps this out of scope and says so; a leaf per machine is a later
   question, noted so it is not forgotten.
-- **The predecessor's world.** It is AMQP, it cannot move, and it does not need to: its broker is
-  the compatibility module until its last client is gone.
+- **The predecessor's world.** It is AMQP and it is not moving —
+  [ADR 0130](../../02-DECISIONS/0130-the-predecessor-is-ending-and-its-broker-goes-with-it.md): it is
+  deprecated, some of it is still running, and it is being left to stop rather than migrated. Its
+  broker goes with it, unassigned like any provider whose provision nothing requires.
 
 ## How this list is kept true
 

03-DESIGN/01-to-be/29-a-node-has-operator-accounts.md

@@ -5,7 +5,10 @@ code: []
 updated: 2026-09-27
 decisions:
   - 02-DECISIONS/0112-a-module-definition-names-no-node-mesh-or-path.md
+  - 02-DECISIONS/0120-a-roster-fact-carries-its-format-as-a-template.md
   - 02-DECISIONS/0051-shared-data-is-the-operators.md
+  - 02-DECISIONS/0113-the-vault-makes-every-secret.md
+  - 02-DECISIONS/0117-a-machines-uplink-is-a-seat.md
 ---
 
 # 29 — A node has operator accounts, and the mesh owns what lives under a home
@@ -18,7 +21,7 @@ owned by, who a user service runs as, and — the case that surfaced this — wh
 person's `~/.ssh/config`, `~/.zshrc`, `~/.config`); the mesh, taking those over, kept the machine
 facts and dropped the human one.
 
-Two things are missing, and they are one idea:
+Several things are missing, and they are one idea.
 
 ## 1. The account is a node fact
 
@@ -28,17 +31,14 @@ mesh already knows the node and its address, so `<account>@<node>` is then a com
 because it is exactly the fact that was silently lost — `ssh ace` failed to `ace` because nothing
 in the mesh said ace's account is `ace`.
 
-It is **not** a credential. The account names a login; the key that authorises it is the
-operator's, placed as a secret or an operator-owned file, never minted by the mesh (ADR 0051).
-
 ## 2. A resource may live under a home, owned by its account
 
 [ADR 0112](../../02-DECISIONS/0112-a-module-definition-names-no-node-mesh-or-path.md) placed a
 module's *system* data — `<root>/<module>`, owned by the module. It has no analog for the other
 half of the filesystem: the things that belong under a person's home and are owned by that
-person. `~/.ssh/config`, `~/.ssh/config.d/mesh`, `~/.zshrc`, `~/.config/hal` — every one of these
-is a resource the mesh should be able to place and own, resolved against **the account's home**
-rather than a system root, and chowned to **the account** rather than to root or a module uid.
+person. `~/.ssh/config`, `~/.zshrc`, `~/.config/hal` — every one of these is a resource the mesh
+should be able to place and own, resolved against **the account's home** rather than a system
+root, and chowned to **the account** rather than to root or a module uid.
 
 This is the same move as `${dir:…}`, one level over: a resource says `home: <account>` (or names
 an account requirement), and the mesh resolves the home directory and the owning uid on the node
@@ -46,39 +46,133 @@ that account lives on. A module that writes operator config — the eventual rep
 `hal/terminal`, `hal/claude-code`, `hal/secrets` — declares its files this way and names no
 `/home/...` path, exactly as a system module now names no `/var/lib` path.
 
+These are a **family**, not one module: an `ssh-client` module, a shell module, a `~/.config`
+module, each a *universal-tier* consumer of the account fact — assigned wherever a person logs in,
+which is every node, unlike the graphical stack that a capability gates.
+
+## 3. The whole of `~/.ssh` is the mesh's — with one boundary drawn inside it
+
+The predecessor owned a single file (`~/.ssh/config`) and left the rest alone; it drifted, because
+owning one file beside foreign ones is not owning anything. The mesh should own **the directory**:
+create `~/.ssh` at `0700`, chown it to the account, and own the files it places there —
+
+- **`config`** (or the mesh's region of it): the `Host` blocks for every other node, composed
+  from the roster;
+- **`known_hosts`**: authoritative, so the "Host key verification failed / accept-new" dance that
+  cost real time during enrolment simply ends;
+- **`authorized_keys`**: who may log into this account, governed centrally rather than by whichever
+  key happened to be pasted where.
+
+**The boundary — and it is the reason this is safe:** `~/.ssh` is the one directory where a wrong
+declaration locks a person out of their own machine. So the mesh's *found-vs-owned* semantics
+([ADR 0126](../../02-DECISIONS/0118-undeclaring-gives-a-unit-back-the-state-it-was-found-in.md),
+adoption) apply *inside* the home directory. The mesh **owns** the directory and the files above; it
+**holds as found — never rewrites, never removes** — the operator's own contents: their **private
+keys** and their **personal drop-ins** (`config.d/personal`, the personal `Host` aliases a
+workstation carries, exactly as `hosts.local` is the home the mesh never rewrites for `/etc/hosts`).
+Reconcile removing an unassigned `config.d/mesh` is fine; the same logic aimed at `id_ed25519` or an
+operator's own `authorized_keys` entry is a lockout. This is the login-channel cousin of the rule
+[ADR 0125](../../02-DECISIONS/0117-a-machines-uplink-is-a-seat.md) draws for the uplink and the sshd
+module draws for the firewall: **the mesh must never be able to arrange the one failure that severs
+its own way back in.** The carve-out is not a convenience; it is that rule, in `~/.ssh`.
+
+## 4. Keys are the mesh's to generate — through a CA, and existing keys are adopted, not replaced
+
+Key *generation* is the mesh's, not each node's improvising its own. The clean form is an **SSH
+certificate authority as a seat**, the sibling of the TLS internal CA the mesh already runs:
+
+- **Host certs.** The mesh signs each node's host key. Every node's `known_hosts` becomes one line
+  — `@cert-authority *.<suffix> <mesh-CA-key>` — and nothing is distributed per node; a new node is
+  trusted the instant its host key is signed.
+- **User certs.** The mesh signs a cert naming the principals (accounts) allowed. Every node's
+  `authorized_keys` / sshd `TrustedUserCAKeys` becomes one trust line — no N×N key spraying — and
+  short-lived certs give rotation for free
+  ([ADR 0114](../../02-DECISIONS/0114-a-shared-credential-rotates-over-two-credentials.md)).
+- The **CA private key is the mesh's**, a secret the vault makes
+  ([ADR 0113](../../02-DECISIONS/0113-the-vault-makes-every-secret.md)).
+
+**Three kinds of key, and only one is never minted.** Host keys (server identity) and pure
+machine-to-machine keys the mesh may generate end to end. The operator's **personal** private key —
+possibly on a hardware token, possibly used from an off-mesh laptop — the mesh **signs into a cert
+but never generates**; that, and only that, is the residue of
+[ADR 0051](../../02-DECISIONS/0051-shared-data-is-the-operators.md). So "keys are mesh-owned" and
+"the operator's login key is the operator's" reconcile: the mesh owns the CA and the signing; it
+holds the human's private half, never mints it.
+
+**Existing keys are not lost.** Taking ownership is *adoption*, not regeneration: a key already on a
+machine is recorded and signed, not overwritten. The mesh gains authority over `~/.ssh` — it does
+not clear it. An enrolling node's host key and the operator's existing key are carried forward; the
+found-vs-owned boundary of §3 is exactly what guarantees nothing already there is destroyed.
+
+## 5. How it is distributed: the controller composes, the node applies
+
+None of this needs a node to discover the mesh, and none of it needs a control-plane module of its
+own. The ssh files are **roster facts**
+([ADR 0128](../../02-DECISIONS/0120-a-roster-fact-carries-its-format-as-a-template.md)): once the
+roster view carries a node's **host key** and its **account** beside its name and address, the
+`ssh-client` module ships a template for `known_hosts`, `config` and `authorized_keys`, and the
+controller renders each node's copy from the full roster and pushes it. The mesh owns the data; the
+module owns ssh's format; the control plane gains no ssh syntax. It is the same act as composing a
+peer list or `/etc/hosts` — which is why there is **no novox-only "mesh-ssh" module**: the
+centralization is the controller's composition, not a module that runs somewhere. Only non-secret
+facts travel (names, addresses, accounts, host keys, the CA public key); the private key stays the
+operator's, placed as an operator-owned file, referenced by path.
+
+## 6. The two modules, and the seat between them
+
+- **`sshd`** (server, every node) — manages sshd, owns and **reports** its host key so the roster
+  carries it, and trusts the user CA.
+- **`ssh-client`** (client, every node) — owns `~/.ssh` per §3, consumes the roster and the CA
+  public key.
+- **`the-ssh-ca`** (a seat, held on the control node) — signs host and user certs.
+
+They meet at the account and the CA, not at a bespoke module. The `sshd` server side already exists;
+the client/identity side and the CA are the open pieces.
+
 ## Why now, and why not yet
 
-**Why it matters:** when HAL retires, the generators that keep `~/.ssh/config`, shell config and
-the operator's `~/.config/hal` current retire with it. Without this, adding a node stops adding
-its ssh alias, and a fresh machine has no operator dotfiles at all — the mesh would run every
-service and leave the human unable to work on the box. The account is also load-bearing for
-correctness already: `ssh <node>` (issue 122's cousin), user-scoped systemd units, and any file a
-person rather than a daemon must own.
+**Why it matters:** when HAL retires, the generators that keep `~/.ssh`, shell config and the
+operator's `~/.config/hal` current retire with it. Without this, adding a node stops adding its ssh
+alias and its trust, and a fresh machine has no operator dotfiles at all — the mesh would run every
+service and leave the human unable to work on the box.
 
-**Why not build it reflexively:** it is a real addition to the node model and the resource model,
-and it must be gotten right, not smuggled in beside a firewall fix. Open questions to settle
-first:
+**Why not build it reflexively:** it is a real addition to the node model, the resource model, and
+the seat set, and must be gotten right. The mechanism half is now settled — ADR 0128 is what lets
+the ssh files be templates with no control-plane format — so what remains to decide here is the
+model:
 
 - **One account or several per node?** A workstation has one human; a shared box might have more.
-  The model should allow more than one without forcing the common case to name it.
-- **Where the login key lives.** An operator-owned file (ADR 0051) or an accepted secret — never
-  minted. The account fact and the key that authorises it are separate, and only the first is the
-  mesh's to generate.
-- **The boundary with `sshd`.** The `sshd` module (server side) already exists. This is the
-  *client* and *identity* side: the account a node offers, and the home-scoped files an operator
-  needs. They meet at the account but are not the same module.
-- **Multi-operator.** Today there is one human. The model should not assume it, but the first
-  cut may serve one and leave the shape open.
+  Allow more than one without forcing the common case to name it.
+- **The CA's shape.** Host-cert and user-cert principals, cert lifetime and renewal, where the CA
+  runs (a seat on the control node). The one thing fixed: the operator's personal key is signed,
+  never minted.
+- **Adoption of existing keys.** How an enrolling node's host key and an operator's existing key are
+  recorded and signed rather than replaced — the found-vs-owned boundary, made concrete for keys.
+- **The `sshd` boundary.** Server side exists; this is the client, the identity, and the CA.
+- **The ssh-agent.** An agent is a *user-scoped service running as the account* — the first concrete
+  case of the user services §2 anticipates. It holds the operator's private key in memory; the mesh
+  declares the unit and sets `AddKeysToAgent`/`IdentityAgent` in `config`, and still never sees the
+  private half. Agent *forwarding* wants a policy, not a default: with user certs it is largely
+  unnecessary, and forwarding an agent into a node exposes the operator's keys to that node's root —
+  so prefer certificates and `ProxyJump` over forwarding.
 
-**Not urgent, not blocking.** ssh and dotfiles work today because HAL's generators still run as
-the substrate. This becomes load-bearing in the node-by-node retirement phase, not before — which
-is the right time to build it, once the account model is decided here.
+**Not urgent, not blocking.** ssh and dotfiles work today because HAL's generators still run as the
+substrate. This becomes load-bearing in the node-by-node retirement phase, not before — which is the
+right time to build it, once the account and CA model are decided here.
 
 ## References
 
 - The gap was found generating `~/.ssh/config` from the *HAL* registry (`hal/terminal`'s
   postConfigure hook), which the nox mesh has no equivalent for.
+- [ADR 0128](../../02-DECISIONS/0120-a-roster-fact-carries-its-format-as-a-template.md) — the roster
+  fact mechanism that renders the ssh files, format owned by the module.
 - [ADR 0112](../../02-DECISIONS/0112-a-module-definition-names-no-node-mesh-or-path.md) — the
   system-path placement this mirrors for home paths.
-- [ADR 0051](../../02-DECISIONS/0051-shared-data-is-the-operators.md) — why the login key stays
-  the operator's, never minted.
+- [ADR 0051](../../02-DECISIONS/0051-shared-data-is-the-operators.md) — why the operator's personal
+  key is signed, never minted.
+- [ADR 0113](../../02-DECISIONS/0113-the-vault-makes-every-secret.md) — the CA key is a secret the
+  vault makes; [ADR 0114](../../02-DECISIONS/0114-a-shared-credential-rotates-over-two-credentials.md)
+  — short-lived certs as rotation.
+- [ADR 0125](../../02-DECISIONS/0117-a-machines-uplink-is-a-seat.md),
+  [ADR 0126](../../02-DECISIONS/0118-undeclaring-gives-a-unit-back-the-state-it-was-found-in.md) —
+  the never-sever-the-channel rule and the found-vs-owned semantics, applied here to `~/.ssh`.

03-DESIGN/01-to-be/30-the-mesh-updates-itself-on-a-push.md

@@ -0,0 +1,137 @@
+---
+layer: to-be
+status: proposed
+code: []
+updated: 2026-09-27
+decisions:
+  - 02-DECISIONS/0121-a-system-seat-is-named-for-its-scope-and-modules-define-their-own.md
+  - 02-DECISIONS/0120-a-roster-fact-carries-its-format-as-a-template.md
+---
+
+# 30 — The mesh updates itself on a push
+
+**Today the mesh does not update itself; a person drives the pipeline by hand, and one class of
+change freezes it.** A code change lands in `mesh-controller` or `mesh-catalog`, and getting it onto
+the machines is a sequence somebody types. The predecessor's pipelines rebuilt and redeployed on a
+push without anyone watching; the successor should too. This records the process as it is done by
+hand now — so it can be read, and then coded — and the two things that make it more than "add a
+webhook".
+
+## The process, as done by hand
+
+**An ordinary (non-breaking) change** — new module code, a bug fix, a manifest tweak that changes no
+seat or schema:
+
+1. `module moved <module> <commit>` — tell the mesh its source advanced (the controller repo has no
+   trigger, so this is manual; the catalogue's webhook does it automatically — see below).
+2. `build --behind` (or `build <repo> [--ref] [--path <subdir>]`) — the build machine rebuilds and
+   records the new image.
+3. The mesh **reconciles on its own**: the module's declaration now names the new image, the next
+   push/heartbeat sends it, and the host swaps the container. For the control plane this is a
+   self-upgrade — the running controller composes its own new image and the host replaces it. No
+   restart is typed.
+
+**A breaking change** — a manifest schema the controller parses differently (a fact's shape, a
+seat's name), where the new control plane cannot read the manifests the old one stored:
+
+4. Land the code (controller + catalogue together — they are one change).
+5. Rebuild + deploy the new controller (steps 1–3). **The moment it is live it refuses the
+   still-old-shape stored manifests, and composition freezes for every node that runs an affected
+   module.** Running services are untouched; only new declarations stop.
+6. **Re-register each affected manifest under the new shape**, which the *new* controller accepts —
+   `module add <file> -source <repo> -ref <ref> -commit <commit>`. This writes the manifest to the
+   store without a build, so it is the fast way to lift the freeze. (The controller container is
+   distroless: `docker cp` the file to the container root `/x.json`; `/tmp` does not exist; the
+   root filesystem is writable. The file is lost when the container is recreated on the next image
+   swap, so copy it *after* the swap.)
+7. `push --behind`, then verify `status` is clean and `seats` (or the relevant surface) shows the
+   new shape held by the right holders.
+
+The freeze in a breaking change has been paid three times in one session (a fact-shape change, the
+`/etc/hosts` region, a seat rename); each time it lasted seconds and no service dropped. It is
+recoverable, but it is not something a push should trigger unwatched — which is the crux of what
+automating this must solve.
+
+## Why it is more than "add a webhook"
+
+### 1. The trigger today is HAL's, not the mesh's
+
+Build-on-push works for the catalogue because its repository has a Gitea webhook pointing at
+`http://host.docker.internal:9877/webhook/gitea` — and **that receiver is `hal-gitea-tools.service`**
+(`~/.hal/modules/hal/gitea/tools/server.js`), a *predecessor* component. The nox builder consumes
+build work; it does not receive Git events. So the mesh's own build pipeline currently rides on a
+HAL service, and:
+
+- the `mesh-controller` repository was never wired to it, which is why the control plane is the one
+  thing that does **not** self-update — every controller deploy this session was `module moved` +
+  `build` by hand;
+- when HAL is retired, build-on-push stops for the whole mesh.
+
+**The mesh needs its own forge-webhook→build trigger**, a nox component (a module, and likely a
+seat — `mesh-forge-trigger` or folded into the git seat's holder) that receives Git events and turns
+them into build work over the broker, for **every** repository including `mesh-controller`. Replacing
+`hal-gitea-tools` is the concrete first build. Its logic already exists to copy: match the pushed
+repository (and changed paths, for a monorepo like the catalogue) against the build-context
+repository of every registered module, and rebuild the matches.
+
+### 2. The builder validates too — and a breaking change deadlocks it
+
+The build machine embeds the same catalogue package the controller does, so **it validates a
+manifest against its own compiled-in seat/schema set**. A breaking change therefore couples *four*
+things, not two: the controller, the **builder**, every affected manifest, and every node's host.
+This session's seat rename rebuilt the controller but not the builder, and the stale builder then
+refused every manifest claiming a renamed seat.
+
+Worse, one rename **deadlocked** the builder: the build machine's own seat was renamed
+(`the-build-machine` → `mesh-build-machine`). To refresh the builder you must build it; to build it
+the *running* (old) builder must accept the new builder's manifest — which claims the new name it
+does not know. The old builder cannot build the new builder. Escapes:
+
+- **Never rename a seat whose holder validates manifests** in an ordinary pass — the build machine's
+  seat belongs with the deferred delivering seats (ADR 0121). Reverting `mesh-build-machine` to
+  `the-build-machine` (deferred) lets the old builder build the new builder, which then knows the
+  new names.
+- Or bootstrap a new builder image **out of band** (build locally, publish to the registry, register
+  the module at that digest), the way genesis loads the first builder — bypassing the old builder's
+  validation once.
+
+Either way, self-update for breaking changes needs a **transition discipline** so a push does not
+auto-freeze: the new control plane (and builder) should accept the *old and new* shape together for
+one release — deprecated aliases in the seat set, a schema that reads both — then a later release
+drops the old. With that, a breaking change rolls out on a push like any other: everything reads
+both, the manifests migrate, the compatibility is removed. Without it, self-update would simply
+automate the freeze.
+
+## What to build
+
+- **A nox forge-webhook trigger** (replaces `hal-gitea-tools`): receives Git events for every mesh
+  repository, dispatches build work to the builder over the broker, and records `module moved`
+  automatically. Wire `mesh-controller` to it so the control plane self-updates like everything else.
+- **A transition discipline for breaking changes**: the control plane and builder accept old+new for
+  one release; the tooling that lands a schema/seat change emits the compatibility shim and the
+  follow-up that removes it. This is what makes step 4–7 above safe to trigger unwatched.
+- **Config/package modules need no builder** — `module add` registers their manifest directly
+  (this is how the uplink managers and the re-registrations above were done). Only image-bearing
+  modules need the build machine, which narrows what the deadlock above can block.
+
+## Why now, and why not yet
+
+**Why it matters:** self-update is the difference between a mesh a person maintains by typing
+pipeline steps and one that maintains itself, and it is a stated goal (parity with the predecessor's
+pipelines). The HAL trigger dependency also makes it a retirement blocker: build-on-push dies with
+HAL.
+
+**Why not reflexively:** the trigger is a new component with the broker and forge in its blast
+radius, and the transition discipline changes how every breaking change is written. Both should be
+designed, not bolted on beside a freeze. The manual process above is the interim, and it works.
+
+## References
+
+- [ADR 0121](../../02-DECISIONS/0121-a-system-seat-is-named-for-its-scope-and-modules-define-their-own.md)
+  — the seat rename whose migration and builder deadlock this record is drawn from
+- [ADR 0128](../../02-DECISIONS/0120-a-roster-fact-carries-its-format-as-a-template.md) — the
+  fact-shape change that first showed the breaking-change freeze
+- `hal-gitea-tools.service` (`~/.hal/modules/hal/gitea/tools/server.js`) — the predecessor webhook
+  receiver on `:9877` the mesh currently rides on
+- mesh-controller `cmd/mesh-builder` (the build machine), `internal/catalogue` (the seat/schema
+  validation the builder shares with the controller)

03-DESIGN/01-to-be/31-a-module-declares-its-fail2ban-jail.md

@@ -0,0 +1,65 @@
+---
+layer: to-be
+status: proposed
+code: []
+updated: 2026-09-27
+decisions:
+  - 02-DECISIONS/0112-a-module-definition-names-no-node-mesh-or-path.md
+---
+
+# 31 — A module declares its fail2ban jail, and the mesh composes them per node
+
+**A node's intrusion filter should be composed from the modules it runs, the same way its firewall
+is.** The mesh already derives a node's nftables ruleset from every assigned module's `listens` and
+`guards` (the `Filtering` mechanism). fail2ban is the same shape and is not modelled: a module that
+runs an authenticating service — postgres, mssql, mailu — has a jail (a filter that reads its log
+and a jail stanza that bans on it), and which jails a node's fail2ban runs should be exactly the
+jails of the modules assigned to that node.
+
+The predecessor did this with per-module files: `postgres` shipped `postgres-auth.conf`, `mssql`
+shipped `mssql-auth.conf`, `mailu` shipped `mailu.conf`, and the node's fail2ban read whichever were
+present. When HAL retired on novox those became dangling symlinks — fail2ban ran the jails only from
+memory, and a restart would have dropped them. The base was salvaged (the fail2ban module now ships
+`sshd`, `recidive`, and the `ignoreip` that spares the mesh's own range), but the **service jails
+are gone**, because no nox module declares one yet.
+
+## The shape
+
+- **A module declares its jail in its manifest**, naming no node and no path (ADR 0112): the filter
+  (the failregex, or a stock filter it uses) and the jail stanza (port, logpath, maxretry, bantime).
+  The `postgres` module says what a postgres brute-force looks like and how to ban it; it does not
+  say on which machine, because it does not know.
+- **The mesh composes them per node.** For each node, the jails of its assigned modules are gathered
+  and written into the fail2ban holder's `jail.d/` (and filters into `filter.d/`), exactly as
+  `listens`/`guards` are gathered into the node's firewall. So a node running postgres gets the
+  postgres jail; a node not running it does not. The `node-intrusion-prevention` holder receives
+  them the way a provider receives its consumers' contributions.
+- **The base stays the fail2ban module's**: `sshd`, `recidive`, and the `ignoreip` naming
+  `${machine:mesh-range}` so a tunnel peer is never banned.
+
+## Why this, and not the module writing the file itself
+
+A module could declare a `file` resource at `/etc/fail2ban/jail.d/<x>.conf` directly. Rejected: the
+path is the fail2ban holder's to own (one module owns `jail.d`, as one module owns the firewall
+table), the jail's logpath and defaults want the mesh's composition (the `ignoreip`, the ban action
+the node uses), and two modules writing into one directory is the collision the seat/holder model
+exists to prevent. The module declares *what its jail is*; the holder's composition decides *how it
+lands* — the same split as `listens` (the module says the port; the mesh says the rule).
+
+## Why now
+
+fail2ban on novox currently runs the service jails from memory only; the next restart drops them
+(the `ignoreip` is safe on disk, so the mesh-partition risk is closed, but postgres/mssql/mailu
+auth-banning would be lost). This is the mechanism that restores them properly, and it is needed as
+each of those modules migrates to the other nodes — ace running postgres should get the postgres
+jail, composed from the postgres module's manifest, without anyone editing a node.
+
+## References
+
+- [ADR 0112](../../02-DECISIONS/0112-a-module-definition-names-no-node-mesh-or-path.md) — a module
+  names no node or path; its jail is declared the same way its `listens` are
+- mesh-controller `internal/catalogue/adoption.go` (`Filtering` — the firewall composition this
+  mirrors), `internal/catalogue/manifest.go` (`Listens`/`Guards`, the fields a jail field sits
+  beside)
+- mesh-catalog `modules/fail2ban` (the base: sshd, recidive, ignoreip); the service modules
+  (`postgres`, `mssql`, `mailu`) that will declare jails

03-DESIGN/01-to-be/32-what-a-module-declares.md

@@ -0,0 +1,502 @@
+---
+layer: to-be
+status: in-progress
+code:
+  - mesh-controller internal/catalogue/declaration.go
+  - mesh-controller internal/catalogue/manifest.go
+  - mesh-controller internal/link/serve.go
+  - mesh-controller internal/link/bus.go
+  - mesh-controller internal/broker/nats.go
+  - mesh-controller internal/inventory/nodes.go
+  - mesh-host internal/apply/apply.go
+  - mesh-tools src/main.ts
+  - mesh-catalog modules/mesh-catalog
+updated: 2026-09-28
+decisions:
+  - 02-DECISIONS/0126-a-module-declares-its-own-seats.md
+  - 02-DECISIONS/0131-everything-on-the-mesh-speaks-to-the-broker-seat.md
+  - 02-DECISIONS/0128-the-mesh-bus-is-required-not-ambient.md
+  - 02-DECISIONS/0106-the-bus-is-nats.md
+  - 02-DECISIONS/0041-events-are-a-relationship.md
+  - 02-DECISIONS/0112-a-module-definition-names-no-node-mesh-or-path.md
+  - 02-DECISIONS/0083-one-push-leaves-the-mesh-consistent.md
+  - 02-DECISIONS/0129-a-seat-carries-the-protocol-of-its-role.md
+  - 02-DECISIONS/0135-a-module-version-prepares-its-state-before-it-runs.md
+  - 02-DECISIONS/0136-a-step-gates-its-module-not-the-machine.md
+  - 02-DECISIONS/0134-the-mesh-says-what-it-applied.md
+---
+
+# 32. What a module declares, and what the bus makes of it
+
+**A module that speaks to the mesh requires the bus, and receives what it needs to connect**
+([ADR 0128](../../02-DECISIONS/0128-the-mesh-bus-is-required-not-ambient.md)). What a module
+declares are *relationships*; subjects, streams, consumers and permissions are all derived from
+those, and a manifest never contains one.
+
+> **Revised 2026-09-26.** This document opened by calling the bus *ambient* — "no module requires
+> it, the way no module requires a filesystem". Two counts say otherwise: of 72 modules in the
+> catalogue, **49 take a broker credential and 23 do not**, so an ambient connection would mint an
+> account for a third of the catalogue that never speaks; and the 49 each hand-write the path it
+> lands at, which is provisioning done badly by hand. The bus is required, and a module that does
+> not require it has no account at all.
+
+**The requirement delivers the connection; the declarations shape the authority.** `requires:
+mesh-bus` says *this module talks to the mesh* and grants no subject by itself. `emits`,
+`consumes`, `tools`, `uses` and a declared seat say what it may say and hear. Declaring a subject
+without requiring the bus is incoherent and refused at registration.
+
+This document is the declaration model. [Design 25](25-the-bus-on-nats.md) is the bus itself —
+subjects, streams, accounts, enrolment — and stays the authority on the wire.
+[Design 19](19-the-module-protocol.md) is the specification an SDK implements, and is rewritten
+onto this in step 3 of [ADR 0116](../../02-DECISIONS/0116-the-bus-is-built-in-five-steps.md).
+
+## 1. A module names locally; the mesh derives the subject
+
+This is the load-bearing rule.
+[ADR 0112](../../02-DECISIONS/0112-a-module-definition-names-no-node-mesh-or-path.md) says a module
+definition names no node, mesh or path. A transport address is the same class of thing: if
+manifests held literal subjects, reorganising the subject space would mean editing every module in
+the catalogue, and the mesh would have hundreds of copies of a decision it made once.
+
+| declared | derived |
+|---|---|
+| `emits: order.placed` | publish on `mesh.mod.<module>.event.order.placed` |
+| `consumes: billing.order.placed` | durable consumer on `mesh.mod.billing.event.order.placed` |
+| `tools: status` | queue-group subscription on `mesh.mod.<module>.tool.status` |
+| seat `telegram-sender`, `accepts: send` | work-queue consumer on `mesh.seat.telegram-sender.accept.send` |
+| `uses: telegram-sender` | publish on that seat's `accept` subjects, and nothing else |
+
+**Wildcards, and they are the mesh's rather than a bus's.** *Added 2026-09-27, from
+[issue 127](../../04-ISSUES/127-a-module-event-derives-a-subject-nothing-publishes/00-report.md).* A
+consumer may write `*` for one name and `**` for the rest: `*.download.completed` is that event from
+any module, and `**` on its own is every event in the mesh, which an audit logger wants and says in
+one token. Spelled this way rather than the wire's, for the reason everything else here is local —
+the bus the mesh runs on today spells these `*` and `#`, the one being built spells them `*` and
+`>`, and a manifest naming either would stop being true when the wire changed. An emitted event
+carries no wildcard: it names one event.
+
+**A module publishes under its own name, and an event about a role belongs to the seat.** *Added
+2026-09-27, same source.* The bus enforces that a namespace belongs to the module it is named for, so
+an event named for somebody else cannot be published at all. Where the event is really about a role —
+"the artifact store accepted an image" — the seat is the right home, because that name outlives
+whoever fills it, and a consumer written against the holder's own name breaks when the holder
+changes. **Not yet possible in practice**: seats carry protocol in the manifest and in the permission
+model, and the shared library has no way for a module to publish on one. Until it does, such an event
+lives under the emitting module's own name and the consumer carries that coupling.
+
+**How the rule is checked, because it was not.** *Added 2026-09-27, same source.* Two checks, because
+the mistake happens at two scales. Per manifest, at registration: an event is a local name, and the
+old bus's form is refused with the name to write instead. Across the whole catalogue, as a test:
+where a consumed event's emitter is present, it must emit that event. The second cannot demand a live
+emitter for everything — a module lives in its own repository and may be installed long before the
+one whose events it wants — so it says nothing about an absent emitter and everything about a present
+one. **A subscription that matches nothing is not an error, it is silence**, which is why nothing
+reported thirty-seven manifests being wrong the same way.
+
+**It is `tools:`, not `serves:`.** Revision, found while implementing: the manifest already uses
+`serves` for the facts a consumer needs in order to reach a provision, and two meanings under one
+key in the file a module author reads most is a footgun. Worth noting that until now a module's
+tools were not declared at all — they were known only at runtime, from an environment variable in
+its image — so declaring them is new, and is what lets the mesh check that a module claiming a
+seat answers what that seat's protocol promises.
+
+**The `event` / `tool` / `accept` token is load-bearing, not decoration.** Revision, found while
+defining the streams: a stream is defined by a subject filter, so a namespace holding both a
+module's events and its tool calls cannot be filtered into an events stream without capturing
+every tool invocation in the mesh — and a tool call must never be persisted
+([design 25](25-the-bus-on-nats.md) §3 keeps tools on core NATS, where a lost call is a timeout the
+caller already handles). The kind token is what makes `mesh.mod.*.event.>` a safe filter. The
+first draft of this table had no token, which reads better and cannot be implemented.
+
+**The test this must pass: the manifest survives the wire changing.** Reorganise the subject space
+and every manifest in the catalogue is still correct. That is the property
+[ADR 0039](../../02-DECISIONS/0039-what-the-sdk-holds-and-refuses.md) gave the sdk, applied to
+declarations.
+
+**A handler names an event the way its manifest does.** *Added 2026-09-27, found while fixing issue
+127.* The runtime handed a handler the event name alone, so a manifest declaring
+`consumes: builder.built` produced a pattern that could never match the key it was compared against,
+and a module consuming one event from two emitters could tell them apart only by reading a header.
+The subject already carries the emitter, so the key a module sees names it too — which makes a
+disagreement between a manifest and the code a typo rather than a category error.
+
+## 2. Three namespaces, and nothing else
+
+**Its own** — `mesh.mod.<module>.>`. Its events and its tools. Nothing else may publish into it,
+so an event's source is a fact the bus enforces rather than a claim in the body.
+
+**Seats it holds** — `mesh.seat.<seat>.>`. Full participation: consume what the seat accepts,
+publish what it emits, serve what it serves.
+
+**Seats it uses** — publish only, and only on the `accepts` half. A sender cannot subscribe to a
+seat's inbound subject and watch other modules' traffic, and cannot publish the seat's outbound
+events and lie about outcomes.
+
+A module naming anything outside these three is refused at registration. The whole permission set
+is derivable from the declaration; nobody writes an access rule.
+
+## 3. Queues are derived, never declared
+
+A module says what it reacts to, not how delivery works. Each `consumes` becomes one durable
+consumer; a seat's `accepts` becomes one work-queue consumer with a queue group named for the
+seat. The module does not name them, does not know their names, and cannot misconfigure them —
+and the controller stays the only writer of stream and consumer definitions
+([design 25](25-the-bus-on-nats.md) §3).
+
+**The mesh's own seats carry protocol too.** *Added 2026-09-27,
+[ADR 0129](../../02-DECISIONS/0129-a-seat-carries-the-protocol-of-its-role.md).* A seat declared by a
+module says what it accepts, emits and serves; the `mesh-*` set said only who does a job. So the mesh
+had roles it could not describe — a build machine with three audiences for one outcome and no way to
+derive a grant for any of them, and an event genuinely about a role with nowhere to live but the
+namespace of whichever module happens to hold it. The mesh's seats now take the same three fields, and
+the same machinery derives the holder's authority, its work queue and its consumers.
+
+**So a build is work submitted to a role, like any other.** The build machine seat accepts a build and
+emits an outcome, and the dedicated branch that carried builds retires: a work queue shared by several
+machines is exactly what `accepts` already is, and a second mechanism for it is two places a permission
+can be wrong.
+
+**And one publish reaches three audiences without anybody's inbox being opened.** A build's outcome is
+the seat's own event: whoever asked matches it by the id their request carried, the controller records
+it, the catalogue places it in the graph. That is the fan-out a shared exchange gave for free, written
+as a subject the mesh derived instead of a topology somebody configured — and it is why a holder needs
+no permission to publish into an asker's inbox, which is the one grant design 25 §4 refuses by name.
+
+**Retention belongs to whoever owns the namespace, not to a consumer.** A seat declares how long
+its inbound backlog survives, because that is a property of the service:
+
+```
+seat: telegram-sender
+  scope: mesh
+  accepts: send        retain 7d
+  emits:   delivered, failed
+  serves:  status
+```
+
+If each consumer could tune it, the mesh's durability would be an emergent property of whichever
+manifest was edited last.
+
+**Why a module's own events do not carry their own retention, though the same rule would allow
+it.** A seat owns its namespace and gets a stream of its own, so it can say. A module's events
+share one `EVENTS` stream, and three facts about JetStream decide that they must:
+
+- **Storage is not a property of a subject.** A subject is only an address; a *stream* is a
+  separate object that captures subjects matching a filter. So "this topic is durable" is always
+  really "some stream covers it", and something has to create that stream.
+- **Overlapping streams are refused, not merged.** Verified against the server: a per-module
+  stream beside a shared `mesh.mod.*.event.>` is rejected with *subjects overlap with an existing
+  stream*. So "one stream by default, its own for a module that wants different retention" is not
+  available — it is all of one or all of the other, and a filter cannot express an exception
+  either.
+- **A stream per module breaks cross-module consumption.** An audit logger consuming every
+  module's events is one consumer on one stream today; with a stream each it becomes one consumer
+  per module, created and destroyed as modules come and go.
+
+So: one stream, and **per-subject caps** for the fairness that actually matters — a noisy emitter
+cannot evict a quiet one, which is verified (a cap of three, ten messages on one subject and one
+on another, leaves four). What is genuinely unavailable is a different *age* per module, because
+JetStream ages per stream and not per subject. A module that truly needs its own retention has a
+way to say so: declare a seat, which owns its namespace and gets its own stream.
+
+**Scope gives per-node workers without a new concept.** A module running on three nodes that each
+need their own queue declares a node-scoped seat: one holder per node, three queues, same
+machinery. Mesh-scoped and node-scoped seats already exist; here they do the work of "one shared
+service" versus "one worker per machine".
+
+## 4. Five relationships
+
+| | provision | event | job | state | tool |
+|---|---|---|---|---|---|
+| shape | 1:1 resource | 1:many | N:1 | 1:1 | 1:1 |
+| addressed to | a provider | the emitter's own namespace | a **seat** | one node | a module or seat |
+| who must act | the provider | nobody | exactly one holder | that node | the server |
+| credential | sealed, per consumer | none | none | none | none |
+| reply | — | none | none, or an event later | a report | awaited |
+| retention | — | age and size | work queue, explicit ack | **last per subject** | none |
+| declared | `provides`/`requires` | `emits`/`consumes` | seat `accepts` / `uses` | the mesh's own | `serves` |
+
+**Job** is the one [ADR 0041](../../02-DECISIONS/0041-events-are-a-relationship.md) had no room
+for. Its table has events at 1:many and provisions at 1:1; a module submitting work to a service
+is neither. It is not an event, because an event is a broadcast nobody is obliged to act on and a
+second holder would do the work twice. It is not a provision, because there is no resource and no
+credential. What makes it safe is not cleverness in the subscribe call but the seat: exactly one
+holder, so exactly one worker, by construction.
+
+**State** is the shape the deploy path needs and nothing else uses. A declaration is not an event
+— replaying yesterday's is actively harmful — and not a job. Only the newest matters, which is
+last-per-subject retention, and a node that has seen sequence *n* refuses *n−1* by construction.
+That is the wire-level answer to
+[issue 107](../../04-ISSUES/107-a-declaration-carries-no-order/00-report.md).
+
+## 5. Seats
+
+A module declares a seat with its protocol, and the mesh enforces one holder at its scope
+([ADR 0126](../../02-DECISIONS/0126-a-module-declares-its-own-seats.md)). A caller declares that
+it uses the *seat*, never the module, so the implementation can be replaced under it.
+
+- The set of seats is **derived** — the mesh's own, plus every registered module's — so it is both
+  closed and extensible, and enumerating it is a query rather than an inventory.
+- `mesh-*` is **reserved**: the prefix is the reservation rule, and a module declaring one is
+  refused at registration.
+- Two modules declaring the same name: the second is refused.
+- A module may not claim a seat whose protocol it does not implement.
+- **Nobody holding a seat is not an error.** The stream exists from registration, so work queues
+  until a holder appears. Install the telegram module a week later and the backlog flushes.
+
+## 6. The lifecycle: build, publish, deploy
+
+Every shape above appears once, in order, and no step knows where the next one runs.
+
+**A change lands.** The module holding `mesh-git` emits `pushed` — repository, ref, commit. An
+event, because it is a fact about git and git's identity is the meaning.
+
+**The change becomes work.** The controller consumes `pushed`, asks the catalogue which modules
+are built from that repository and path
+([ADR 0069](../../02-DECISIONS/0069-a-module-is-a-repository-and-a-path.md)), and submits one
+**job** per affected module to the `mesh-build-machine` seat. The builder stays simple: it builds
+what it is handed, and never resolves anything. A builder that dies mid-build has its job
+redelivered, because a work queue with explicit ack is what that means.
+
+**The artifact is published.** The builder pushes to the registry seats and emits `built` —
+module, version, digest. An event again: a fact about the builder.
+
+**The build cascade is that event fanning out through a graph the mesh already has.** A module
+whose image is built *on* another's artifact declares that in `build.on`. So `built` reaches the
+controller, which walks the declared graph and submits rebuild jobs for everything downstream. A
+dependency cascade is not special machinery — it is one event, one derived graph, and the same job
+queue.
+
+**Deployment is state, not a message.** The controller composes each affected node's declaration
+and publishes it last-per-subject. A node that was away gets exactly the current one, never a
+queue of superseded ones, and a replayed older one is refused by sequence.
+
+**A version prepares its state before it runs.** *Built 2026-09-28.* A module version may declare an
+entrypoint that brings its state to the shape that version needs — the same vocabulary as the entrypoints it declares for its
+tools and its provisioner, and nothing about how a machine runs it. The mesh runs that entrypoint as it
+runs the module's own code, to completion, in the module's own context, and a version whose preparation
+did not succeed does not run: the step gates that module and nothing else on the machine
+([ADR 0136](../../02-DECISIONS/0136-a-step-gates-its-module-not-the-machine.md)), and the rollout stops
+at the first machine that did not take it
+([ADR 0135](../../02-DECISIONS/0135-a-module-version-prepares-its-state-before-it-runs.md), superseding
+[ADR 0133](../../02-DECISIONS/0133-a-module-owns-its-migrations-and-the-mesh-owns-when-they-run.md)).
+Once per state, and the mesh derives what a state is: a consumer is a module on a machine, so what the
+mesh provisions is per consumer and preparation is too. No level to choose, and no race to lock against.
+
+**Applying is reported to a role.** The host applies and reports to the `mesh-controller` seat —
+not to an address it was given at genesis. Held and retried while the store restarts
+([ADR 0083](../../02-DECISIONS/0083-one-push-leaves-the-mesh-consistent.md)).
+
+**And the mesh says what it applied.** *Built 2026-09-28.* A report is control traffic only the control plane reads, so the
+chain above went dark at the moment it touched a machine: nothing said which version a machine now runs,
+or that it refused to. The control plane states those as facts under its own seat's namespace, when what
+a machine runs changes rather than on every convergence pass, and anything that cares subscribes the way
+the catalogue subscribes to `built` ([ADR 0134](../../02-DECISIONS/0134-the-mesh-says-what-it-applied.md)).
+The facts are second-hand by design — one emitter, one ordering — and a machine that cannot reach the bus
+produces none, so absence is not health.
+
+What disappears across that chain is every address. No webhook URL, no registered callback, no
+"which node is the builder on", no controller endpoint baked into a joining node. That is the
+class of bug
+[issue 102](../../04-ISSUES/102-an-address-recorded-at-genesis-or-build-does-not-follow-the-nodes-ports/00-report.md)
+names, dissolved rather than fixed.
+
+## 7. Modules depending on each other
+
+Three kinds, and conflating them is how deployment ordering goes wrong.
+
+**Build-time** — A's image is built on B's artifact. Resolved by the cascade above; nothing at
+runtime cares.
+
+**Provision** — A requires a database from B. A **hard** dependency: the credential must exist
+before A can start, so resolution gates delivery and A is shown as waiting until B has answered
+([design 27](27-a-module-requires-the-mesh-resolves.md)).
+
+**Seat** — A uses B's seat. A **soft** dependency, and this is the one the bus changes. A starts
+whether or not anyone holds the seat, because the stream absorbs the gap. Deployment order stops
+mattering for everything expressed this way, and a service being restarted, moved or upgraded is
+not an outage for its callers — it is latency.
+
+That difference is worth choosing on purpose. A dependency expressed as a provision must be
+ordered; the same dependency expressed as a seat need not be.
+
+## 8. Versioning a protocol
+
+A seat's protocol is a compatibility surface between modules that do not know each other and are
+deployed at different times. Four ways it can change, and they are not equally dangerous:
+
+| change | example | detectable |
+|---|---|---|
+| **additive** | a new `accepts` subject, a new optional field | nothing breaks |
+| **removal or rename** | `send` becomes `deliver` | yes, mechanically |
+| **shape** | an optional field becomes required | yes, if shapes are specified |
+| **semantic** | `send` starts meaning *queue for tomorrow* | **no** |
+
+**Additive is free.** A seat may grow without a version, without re-registering a caller, and
+without ceremony. Most change is this.
+
+**A breaking change is refused while anyone is bound.** Registration computes a compatibility
+fingerprint over the seat's protocol — its subjects and the shapes they carry. A registration that
+alters the fingerprint while callers are bound is refused, **and the refusal names them**. The
+mesh already holds the `uses` graph, so this is derived rather than declared, and it turns a
+runtime breakage into a registration-time conversation.
+
+**When a break is genuinely needed, the version goes in the subject, not the name.** The seat stays
+one thing; `mesh.seat.<seat>.v2.<verb>` runs beside v1 and the holder serves both. A caller moves
+when it is ready. Versioning the *seat name* was considered and rejected: it forks the role, so
+"one holder" stops meaning one provider of the capability, and every document naming the seat has
+to be found and changed.
+
+**Binding is recorded, not inferred.** A caller declares `uses: telegram-sender` with no version,
+and resolution binds it to the current one and records that — the same **pin** machinery
+[design 27](27-a-module-requires-the-mesh-resolves.md) already uses when resolution had a choice
+to make. Moving to v2 is a deliberate re-pin, so nothing drifts onto a new protocol because it
+happened to be newest.
+
+**Retirement is reported, never automatic.** When the `uses` graph shows nothing bound to v1, the
+overview says it is retirable. The mesh does not remove it.
+
+**And none of this catches a semantic change.** Same subject, same shape, new meaning: no
+fingerprint sees it, and no check proposed here would. The defences are review, and pushing
+meaning into shape wherever it can go — a required `channel` field is caught, a changed
+interpretation of an existing one is not. Saying so is better than implying the fingerprint is
+complete, because a team that believes it is complete stops reviewing for the case it misses.
+
+## 9. Provisioning over the bus
+
+Provisioning rides the bus, and the provider stops having an address.
+
+| part of a provision | shape |
+|---|---|
+| the requirement resolving to a provider | the controller's, not the bus's |
+| the grant reaching the provisioner | request/reply to a **role** |
+| `holds` — the reconcile question, every minute | the same call, on a timer |
+| `provisioned` / `deprovisioned` | events |
+| the credential reaching the consumer | §10 — fetched, never carried |
+
+A provisioner's interface is already three calls — create, remove, holds — which is exactly a
+`serves` protocol. So **a provision interface is a seat whose protocol is those three**, which is
+why [design 26](26-the-seats.md) already allows a seat to deliver a provision. The two concepts
+were converging before this document; here they meet.
+
+What stays different, and must not be unified away: a provision has a **per-consumer resource and
+a sealed credential**, created and destroyed per consumer. A seat protocol has neither — it is a
+role you send to. Collapsing them would mean pretending a database is a subject.
+
+### `mesh-bus` and `nats` are two interfaces, never one name
+
+The mesh's own bus is **`mesh-bus`**, delivered by the `mesh-broker` seat and answered by the
+controller — because the bus's accounts are configuration rather than something a provisioner
+creates, so there is no provisioner process in the path and nothing waiting on a bus account in
+order to make bus accounts. A module that runs a NATS server of its own and offers it as a
+backing service provides **`nats`**, exactly as the deprecated broker provides `amqp`
+([ADR 0127](../../02-DECISIONS/0127-amqp-is-a-provision-not-the-bus.md) (superseded by [ADR 0131](../../02-DECISIONS/0131-everything-on-the-mesh-speaks-to-the-broker-seat.md): AMQP is not a provision, and everything speaks to the `mesh-broker` seat)).
+
+They are never the same name. A manifest saying `nats` could otherwise mean either the mesh's
+nervous system or a private queue, and the difference between those is the whole architecture.
+0119's rule decides which is legitimate: a private bus is a backing service, never a channel to
+another module.
+
+### Where addresses survive
+
+"Where is it?" is two different problems, and the bus solves one of them completely and the other
+not at all. Keeping them apart matters, because a reader who thinks the mesh no longer has
+addresses will believe a class of bug is fixed when it is untouched.
+
+**Something that is on the bus: the address disappears.** A host reporting in used to need the
+controller's address — recorded somewhere, at some moment, and wrong as soon as anything moved.
+Now it publishes to `mesh.seat.mesh-controller.report` and the bus routes it to whoever holds the
+seat. Nothing anywhere records where the controller is, so nothing can record it *wrongly*. The
+same is true of the builder, the catalogue, the telegram sender. This class is not mitigated; it
+is gone, because the information is no longer stored.
+
+**Something that is not on the bus: the address stays, exactly as before.** A module that requires
+a database does not reach postgres over NATS — it opens a postgres connection, because postgres
+speaks postgres and is not listening on any subject. Its credential contains a host and a port,
+and no amount of subject addressing changes that.
+
+So the fix for that second class is unchanged and is not this document's:
+[ADR 0098](../../02-DECISIONS/0098-a-fact-a-provider-makes-at-first-start-is-fetched-from-it.md) —
+fetch the fact where it is used rather than storing a copy — which is what
+[issue 102](../../04-ISSUES/102-an-address-recorded-at-genesis-or-build-does-not-follow-the-nodes-ports/00-report.md)
+is actually about. The bus makes that class *smaller* by removing every mesh-internal address from
+it. It does not make it empty.
+
+**And one address is irreducible: the bus's own.** A node has to know where the broker is before
+it can use subjects for anything, so that one cannot be a subject. It is the addressing equivalent
+of §10's bootstrap — the first thing cannot be found by the mechanism that finds everything else.
+
+## 10. Secrets, and why they never enter a stream
+
+Everything the vault does is request/reply to the `mesh-vault` role: mint, fetch, rotate. In that
+sense it is as much on the bus as anything else.
+
+**The bus is not trusted with a secret, and does not need to be.** A secret is sealed to its
+recipient, so what crosses the bus is ciphertext only that recipient can open. The broker sees
+that a secret moved, and to whom — metadata, which is acceptable — and never a plaintext.
+
+**But sealed is not enough on its own, because a stream persists.** A sealed secret written into
+a JetStream stream is a durable ciphertext sitting in the mesh's own storage, and the day a
+sealing key leaks, that stream is an archive rather than a moment. So:
+
+- **A secret travels on core request/reply, never through a stream.** No persistence, no replay,
+  nothing to exfiltrate later.
+- **A declaration names a secret; it does not carry one.** Declarations are the state shape, which
+  *is* a stream — so the host fetches the secret from the vault at apply time, over the core path.
+  That is [ADR 0098](../../02-DECISIONS/0098-a-fact-a-provider-makes-at-first-start-is-fetched-from-it.md)'s
+  existing discipline — *fetched from it, not carried* — applied to the one payload where carrying
+  it is worst.
+
+**The bootstrap, which is circular and has a precedent.** The vault makes every secret
+([ADR 0113](../../02-DECISIONS/0113-the-vault-makes-every-secret.md)), including the bus's own
+passwords. The vault is a module, and a module needs a bus account, whose password the vault
+makes. Nothing can go first.
+
+This is the shape [ADR 0067](../../02-DECISIONS/0067-genesis-is-a-pivot.md) already resolves for
+the control plane: **genesis is a pivot.** The controller mints the handful of foundation
+credentials itself, raises the store, the broker and the vault, and then the vault takes over and
+mints everything from there — the same move as raising a temporary control plane and reinstalling
+it as an ordinary module once the registry exists.
+
+So there are exactly two things the normal path cannot make, both at genesis, both ending the
+moment the mesh can mint for itself: **the bus's own accounts** (§the bootstrap argument in
+[ADR 0127](../../02-DECISIONS/0127-amqp-is-a-provision-not-the-bus.md) (superseded by [ADR 0131](../../02-DECISIONS/0131-everything-on-the-mesh-speaks-to-the-broker-seat.md): AMQP is not a provision, and everything speaks to the `mesh-broker` seat) (superseding [ADR 0125](../../02-DECISIONS/0125-the-bus-is-the-only-broker.md)) — a provisioner is a module and
+needs an account before it can run) and **the vault's own credential**. Any third exception is a
+design failure, and naming these two is what makes a third one visible.
+
+## 11. Open
+
+**Semantic change has no mechanical defence** (§8). Recorded as open rather than solved, because
+it is the residue of a question the rest of §8 answers and the part a fingerprint cannot reach.
+
+**Whether a module may declare a seat it does not itself claim** — the contract as one thing, the
+implementation as another, which is how two competing implementations would ever exist.
+
+**Whether a container should have a readiness notion.** Only an action carries `verify`, so a step that
+must run once a service *answers* — seeding through its own API — cannot be declared at all. Named here
+because the steps above make the gap obvious, not because they caused it.
+
+**Whether `consumes` naming another module couples too tightly.** It is kept here deliberately —
+an event's provenance is its meaning — but a consumer of `billing.order.placed` does depend on
+billing existing under that name.
+
+## 12. How it is checked
+
+- **A manifest holds no subject.** A catalogue test: no manifest contains a string matching the
+  subject grammar. The rule is worthless if it is followed by convention.
+- **A preparation is given what the module is given.** A composition test: what the preparation
+  entrypoint receives equals what the module's own code receives, asserted rather than written twice —
+  which is the drift a hand-written step invites, three times over in the catalogue today.
+- **A convergence that changed nothing says nothing.** Two identical reports, one emitted fact: what is
+  guarded against is a fact per minute per machine, which is a stream nobody reads.
+- **Permissions are exactly the three namespaces.** A composition test per module: the derived
+  permission set equals what its declaration implies, and a hand-written addition to it fails.
+- **A sender cannot read the queue it writes to.** A bed: a module declaring `uses` is refused
+  subscribe on that seat's inbound subject.
+- **One holder, one delivery.** A bed: a seat's job delivered once with the holder running, and
+  a second claim of the seat refused.
+- **A queued job survives no holder.** A bed: submit with the seat unheld, assign the holder,
+  the job is delivered.
+- **The cascade rebuilds exactly the dependents.** A bed: publish an artifact two modules build
+  on, and exactly those two are rebuilt.
+- **A stale declaration is refused.** A bed: replay sequence *n−1* after *n*, and the node refuses
+  it rather than applying it.

03-DESIGN/01-to-be/33-the-tools-the-mesh-answers.md

@@ -0,0 +1,137 @@
+---
+layer: to-be
+status: designed
+code: []
+updated: 2026-09-28
+decisions:
+  - 02-DECISIONS/0132-a-seat-carries-the-tools-its-holder-must-serve.md
+  - 02-DECISIONS/0129-a-seat-carries-the-protocol-of-its-role.md
+  - 02-DECISIONS/0095-the-control-plane-is-the-way-to-ask-a-module.md
+---
+
+# 33 — The tools the mesh answers
+
+**An agent can call the mesh's tools and cannot find out what they are.** Both halves were measured
+on the live mesh on 2026-09-28: a client holding an operator credential connected to the bus, asked a
+module for its repositories and got them; the same client's request for the tool list found nothing
+serving it. The transport works, the account model works, the adapter that speaks the agent protocol
+works. What is missing is the mesh being able to say what it can do.
+
+This design is the answer to that question, and it has three families in it, because a tool belongs to
+whoever is accountable for answering it.
+
+## 1. Three families, and why the split is not arbitrary
+
+| Family | Addressed to | Where the definition lives | Example |
+|---|---|---|---|
+| A **role's** tools | the seat: `mesh.seat.<seat>.tool.<verb>` | the seat's protocol, in the mesh's records | ask *the forge* to list its repositories |
+| A **module's** tools | the module: `mesh.mod.<module>.tool.<name>` | that module's code | ask *this gitea* for `gitea_list_repos` |
+| The **mesh's** own verbs | the `mesh-controller` seat | the seat's protocol, as above | `status`, `push`, `build`, `assign` |
+
+The split follows accountability. A role is something the mesh guarantees exactly one holder of, so
+what the role answers is the mesh's to define and a holder's to implement
+([ADR 0132](../../02-DECISIONS/0132-a-seat-carries-the-tools-its-holder-must-serve.md)). A module's
+own tools are nobody's business but the module's, and their definitions live where they are
+implemented, because a copy kept anywhere else drifts from the code that answers.
+
+The mesh's own verbs are the third family only in where they come from, not in kind: the control plane
+holds a seat like anything else, and its tools are that seat's. This is what keeps them addressable
+while the control plane is being replaced, which is the moment they are most needed.
+
+**Both names for one capability is deliberate and bounded to this.** A forge holding the `git` seat
+answers the role's `list_repos` and its own `gitea_list_repos`, because the same module may run
+without the seat — a second instance, kept for one purpose — and then only the second name is true.
+The caller chooses which question it is asking. Nothing else in the mesh gets two names.
+
+## 2. What a seat's tool is
+
+A verb, what it does, and the schema of its arguments and its answer. A name alone is not callable by
+something that has never seen the mesh before, which is the whole population this surface exists for.
+
+The protocol a seat carries today is three lists of bare verbs
+([ADR 0129](../../02-DECISIONS/0129-a-seat-carries-the-protocol-of-its-role.md)), and it must widen to
+carry the rest. Two constraints on that widening:
+
+- **It lives in the mesh's records, not in the control plane's binary.** Today a seat's protocol comes
+  from compiled defaults, merged in as a row is read, because the seat rows never gained the columns.
+  Discovery that reads a binary is discovery that disagrees with the mesh the moment the two are on
+  different versions.
+- **The schema is stated in the form an agent protocol already uses**, so nothing translates between a
+  seat's idea of an argument and the caller's. A translation layer would be a second definition of
+  what a tool is.
+
+## 3. Holding a seat means serving its tools
+
+A module may not occupy a seat unless it serves every verb that seat declares. This joins the
+conditions of holding that already exist — providing what the seat delivers, being assigned at the
+seat's scope — and is refused the same way: at registration and at handover, naming the verbs that are
+missing rather than the fact that something is.
+
+A module knows which seats it claims, so knowing which tools it must serve is not a discovery problem
+for the module: the seat says, the module implements, and anything beyond that is its own.
+
+## 4. Addressing a node-scoped seat
+
+A seat's subject is flat today — `mesh.seat.<seat>.<kind>.<verb>` — which is correct for a seat the
+mesh has one holder of and wrong for the six node-scoped seats, where one subject would reach every
+machine's holder and the holders' queue group would hand the call to whichever answered first. A
+node-scoped seat's tool therefore carries the node it is asked of. Nothing about a mesh-scoped seat
+changes.
+
+## 5. Discovery
+
+**What a role answers is a read.** The seats and their protocols are records, so the list is a query
+against the mesh's own store: no call to a module in the path, nothing that has to be running, and an
+answer that stays true while a holder is restarting or being replaced.
+
+**What a module answers comes from the module.** Its definitions live in its code, so it is asked, and
+the answer is as available as the module is — which is the right coupling for a tool that only exists
+while that module does.
+
+A caller therefore gets one list assembled from two sources, and the difference is visible in it: a
+role's tool names a seat, a module's names a module. An agent that wants to survive a holder being
+replaced binds to the first.
+
+## 6. What serves this to an agent
+
+A module the mesh assigns to the machine where the agent runs, holding a credential the mesh minted,
+with authority derived from what it may call — not a program started by hand with a credential printed
+to a terminal. The adapter itself already exists and is thin by design; what changes is that it stops
+being something a person carries and becomes something the mesh runs, on a node, like everything else.
+
+An agent's authority can then be role-shaped: *the forge's tools*, rather than a list of
+module-specific names that changes the day the forge is replaced.
+
+## 7. Versioning
+
+A seat's tools are an interface and change like one. Additive within a version. A change that would
+break a caller takes the version token the subject already has room for, and the two versions run side
+by side until nothing is bound to the old one.
+
+## How it is checked
+
+- **A holder missing a verb cannot take the seat.** One test per condition of holding, as the existing
+  conditions have, and the live refusal names the verbs.
+- **A verb nobody declared is a subject nobody may use.** The bus grants are derived from the seat's
+  protocol already, and the golden composition of the user list is what keeps that honest: a holder is
+  granted exactly the seat's verbs, a user of the seat exactly the publish side.
+- **Discovery needs no running module.** The test for a role's tools reads records and asserts the
+  answer equals what the seats declare — if it needed a module up, it would not be a read.
+- **Two nodes holding one node-scoped seat derive two addresses.** Checked by the same test as the rest
+  of the subject table.
+
+## What this does not settle
+
+- Which verbs each seat should serve. That is a decision per seat, and the reason to do it slowly: a
+  seat's tools bind every future holder.
+- Whether a module's own tool definitions should also be recorded when a build resolves its manifest.
+  There is an argument for it — the mesh could then answer for a module that is down — and an argument
+  against, which is that a recorded copy of a live definition is a copy that can be wrong.
+
+## References
+
+- [ADR 0132](../../02-DECISIONS/0132-a-seat-carries-the-tools-its-holder-must-serve.md) — the decision this designs
+- [ADR 0129](../../02-DECISIONS/0129-a-seat-carries-the-protocol-of-its-role.md) — a seat carries the protocol of its role
+- [ADR 0095](../../02-DECISIONS/0095-the-control-plane-is-the-way-to-ask-a-module.md) — a tool call passes one process where an audit belongs
+- [`26-the-seats.md`](26-the-seats.md) — what a seat is, how it is held and handed over
+- [`25-the-bus-on-nats.md`](25-the-bus-on-nats.md) §7 — a person's account, their inbox, and the adapter

03-DESIGN/01-to-be/README.md

@@ -35,11 +35,13 @@ document is written and this one's status becomes `implemented`.
 | [`23-choosing-a-provider.md`](23-choosing-a-provider.md) | Which of several providers of a kind serves a consumer, and when a module carries its own instead | [ADR 0084](../../02-DECISIONS/0084-which-provider-serves-a-consumer.md), [ADR 0027](../../02-DECISIONS/0027-a-provision-names-what-the-consumer-is-coupled-to.md) |
 | [`24-the-secrets-vault.md`](24-the-secrets-vault.md) | The module that owns a secret — a `secret` provision, and the boundary of what it owns | [ADR 0085](../../02-DECISIONS/0085-a-secret-is-a-provision.md), [ADR 0031](../../02-DECISIONS/0031-the-control-plane-authenticates-nobody.md), [ADR 0048](../../02-DECISIONS/0048-a-provider-creates-the-credential-the-mesh-minted.md) |
 | [`25-the-bus-on-nats.md`](25-the-bus-on-nats.md) | **Proposed.** The architecture of the mesh's bus on NATS: what rides which subject under which guarantee and whose account, how a node joins, how a person reaches a tool, and how the mesh moves from the bus it has | [ADR 0106](../../02-DECISIONS/0106-the-bus-is-nats.md), [ADR 0116](../../02-DECISIONS/0116-the-bus-is-built-in-five-steps.md), [ADR 0043](../../02-DECISIONS/0043-a-module-broker-account-is-scoped-by-emits-and-consumes.md), [ADR 0083](../../02-DECISIONS/0083-one-push-leaves-the-mesh-consistent.md) |
-| [`26-the-seats.md`](26-the-seats.md) | **Proposed.** What a mesh can have one of, who fills each, and a seat's holder answering for the provision it delivers — including the `git` seat a build's source can live on | [ADR 0110](../../02-DECISIONS/0110-a-seat-is-a-module-assignment-from-a-closed-set.md), [ADR 0111](../../02-DECISIONS/0111-a-build-source-is-on-the-git-seat-or-external.md), [ADR 0109](../../02-DECISIONS/0109-a-package-registry-seat-is-one-per-ecosystem.md) |
-| [`27-a-module-requires-the-mesh-resolves.md`](27-a-module-requires-the-mesh-resolves.md) | **Proposed.** One concept for everything a module needs: a requirement with a contract, answered by one of four kinds of provider, resolved at assignment or refused. Retires settings, placeholders, facts and paths in definitions | [ADR 0112](../../02-DECISIONS/0112-a-module-definition-names-no-node-mesh-or-path.md), [ADR 0113](../../02-DECISIONS/0113-the-vault-makes-every-secret.md), [ADR 0114](../../02-DECISIONS/0114-a-shared-credential-rotates-over-two-credentials.md), [ADR 0110](../../02-DECISIONS/0110-a-seat-is-a-module-assignment-from-a-closed-set.md) |
+| [`26-the-seats.md`](26-the-seats.md) | **Proposed.** What a mesh can have one of, who fills each, and a seat's holder answering for the provision it delivers — including the `git` seat a build's source can live on | [ADR 0126](../../02-DECISIONS/0126-a-module-declares-its-own-seats.md) (superseding [ADR 0110](../../02-DECISIONS/0110-a-seat-is-a-module-assignment-from-a-closed-set.md)), [ADR 0111](../../02-DECISIONS/0111-a-build-source-is-on-the-git-seat-or-external.md), [ADR 0109](../../02-DECISIONS/0109-a-package-registry-seat-is-one-per-ecosystem.md) |
+| [`27-a-module-requires-the-mesh-resolves.md`](27-a-module-requires-the-mesh-resolves.md) | **Proposed.** One concept for everything a module needs: a requirement with a contract, answered by one of four kinds of provider, resolved at assignment or refused. Retires settings, placeholders, facts and paths in definitions | [ADR 0112](../../02-DECISIONS/0112-a-module-definition-names-no-node-mesh-or-path.md), [ADR 0113](../../02-DECISIONS/0113-the-vault-makes-every-secret.md), [ADR 0114](../../02-DECISIONS/0114-a-shared-credential-rotates-over-two-credentials.md), [ADR 0126](../../02-DECISIONS/0126-a-module-declares-its-own-seats.md) (superseding [ADR 0110](../../02-DECISIONS/0110-a-seat-is-a-module-assignment-from-a-closed-set.md)) |
 | [`28-building-the-bus.md`](28-building-the-bus.md) | **Proposed.** The five steps of the bus work in the order their dependencies allow, each ending at a bed — with the surface measured, so no step's size is a guess | [ADR 0116](../../02-DECISIONS/0116-the-bus-is-built-in-five-steps.md), [ADR 0106](../../02-DECISIONS/0106-the-bus-is-nats.md), [ADR 0074](../../02-DECISIONS/0074-the-wire-is-specified-not-the-types.md) |
 | [`29-a-node-has-operator-accounts.md`](29-a-node-has-operator-accounts.md) | **Proposed.** The mesh models machines but not the humans on them: a node gains operator accounts, and a resource may live under a home owned by its account — what would own ~/.ssh, dotfiles and ~/.config when HAL retires | [ADR 0112](../../02-DECISIONS/0112-a-module-definition-names-no-node-mesh-or-path.md), [ADR 0051](../../02-DECISIONS/0051-shared-data-is-the-operators.md) |
 
+| [`32-what-a-module-declares.md`](32-what-a-module-declares.md) | **Proposed.** What a module declares and what the bus derives from it: three namespaces, subjects from local names, queues never declared, the five relationships, and the build-publish-deploy lifecycle on one bus | [ADR 0126](../../02-DECISIONS/0126-a-module-declares-its-own-seats.md), [ADR 0127](../../02-DECISIONS/0127-amqp-is-a-provision-not-the-bus.md), superseded by [ADR 0131](../../02-DECISIONS/0131-everything-on-the-mesh-speaks-to-the-broker-seat.md) (superseding [ADR 0125](../../02-DECISIONS/0125-the-bus-is-the-only-broker.md)), [ADR 0041](../../02-DECISIONS/0041-events-are-a-relationship.md) |
+
 ## Not yet written
 
 - **The remaining six contexts.**

04-ISSUES/112-adopting-a-tunnel-gives-the-mesh-addresses-without-names/00-report.md

@@ -1,5 +1,5 @@
 ---
-status: fixed
+status: resolved
 opened: 2026-09-24
 located-in: [mesh-controller internal/inventory, mesh-controller internal/catalogue, mesh-controller cmd/mesh-controller, mesh-catalog modules/dnsmasq]
 fixed-by: [mesh-controller#73 overlay-name + namesInTheMesh, mesh-catalog#106 dnsmasq daemon.json merge]

04-ISSUES/127-a-module-event-derives-a-subject-nothing-publishes/00-report.md

@@ -0,0 +1,93 @@
+---
+status: resolved
+opened: 2026-09-27
+located-in: [mesh-catalog modules, mesh-control internal/catalogue, mesh-tools src]
+fixed-by: mesh-catalog 7b06a7a, mesh-tools fbeb373, mesh-control 05ff606
+amended-design: 03-DESIGN/01-to-be/32-what-a-module-declares.md
+---
+
+# 127 — A module's event derives a subject nothing publishes
+
+## What was observed
+
+[Design 29](../../03-DESIGN/01-to-be/32-what-a-module-declares.md) §1 says a module names an event
+locally and the mesh derives the subject: `emits: order.placed` becomes
+`mesh.mod.<module>.event.order.placed`, and a consumer declaring `consumes: shop.order.placed`
+subscribes the emitter's own subject. That derivation is built and tested.
+
+**Every event name in the catalogue is still written the way a routing key on the bus the mesh has
+is written** — `module.<module>.<verb>` — and the derivation reads it as `<emitter>.<event>`. Asked
+of the composer directly, with the module names and declarations the catalogue holds today:
+
+| declared | derived |
+|---|---|
+| `builder` emits `module.builder.built` | publish `mesh.mod.builder.event.module.builder.built` |
+| the catalogue consumes `module.builder.built` | subscribe `mesh.mod.module.event.builder.built` |
+| a media module emits `module.<itself>.download.completed` | publish `mesh.mod.<itself>.event.module.<itself>.download.completed` |
+| a player consumes `module.*.download.completed` | subscribe `mesh.mod.module.event.*.download.completed` |
+
+The consumer's subject names a module called `module`. **No cross-module subscription in the
+catalogue matches what any emitter publishes.** Thirty-seven manifests declare events; every one of
+their consume declarations derives this way.
+
+Two further consequences of the same cause, found in the same check:
+
+- One module declares `consumes: "#"` — the wildcard of the bus the mesh has, which is not a
+  subject at all. The composer **refuses it outright**, so that module's account cannot be composed
+  and the module cannot be assigned.
+- One module emits under a name that is not its own — it declares `module.<other>.image.pushed`
+  while being a differently named module — which the derivation puts inside *its* namespace. Whether
+  that is legitimate is a design question: design 32 §2 makes an event's source a fact the server
+  enforces, and this is a module claiming another's name in its own event.
+
+None of it fails on the bus the mesh runs on today, where a routing key is matched literally and
+nothing derives anything. It fails only once the subject is derived — which is to say it fails on
+the first mesh raised on the new bus, and not before.
+
+Evidence: run against the controller's own `PermissionsFor` on the current feature branch, with the
+declarations read from the catalogue's manifests. Found while wiring the controller's consume side
+(design 28 step 3.4), when the controller's own subscription had to be written and the subject it
+would have to name turned out not to be the one design 32 specifies.
+
+## Why it matters beyond this instance
+
+**This is the failure [ADR 0074](../../02-DECISIONS/0074-the-wire-is-specified-not-the-types.md)
+exists to catch, arriving by a route the conformance suite does not cover.** Two implementations
+that disagree about an envelope do not fail to compile — they ignore each other while both keep
+running. Here it is not two implementations disagreeing but a *declaration* and a *derivation*
+disagreeing, and the symptom is identical: every service starts, every log is quiet, and nothing
+reacts to anything.
+
+The fixtures cannot catch it. They pin one emitter's envelope against one subject, and both halves
+of that pair are correct. What is wrong is only visible when an emitter's derived subject is set
+beside a consumer's derived subject — a check nothing performs, because until the subject was
+derived there was nothing to compare.
+
+It also means the rule 3.8 established is weaker than it reads. That task asserted **no manifest
+contains a subject**, which holds: a manifest contains a local name. What nothing asserts is that a
+local name derives to a subject some emitter actually publishes, and the rule as stated is satisfied
+by thirty-seven manifests whose names derive to nothing.
+
+And it blocks work already scheduled. Design 28's step 4.2 (a build source's change reaching the
+builder over the bus) and 4.3 (an installation completing over the bus) are both event flows through
+exactly these pairs, and the catch-up flow the controller answers is a third — the controller
+currently replays a build announcement under its *own* name rather than the builder's, which a
+consumer filtering the builder's subject will not hear either.
+
+## Open questions
+
+- Is a local name converted per manifest (`emits: built`), or does the derivation keep accepting the
+  old form and strip a redundant prefix? The first is thirty-seven manifests and a rule that can be
+  checked; the second is a rule that cannot, because `module.foo.bar` is also a legitimate three-part
+  local name.
+- What checks the pair? An emitter's derived subject against every consumer's derived subject is a
+  whole-catalogue check, not a per-manifest one — and a module lives in its own repository and may
+  be registered long after the catalogue was checked.
+- What are `#` and `*` in a consumed name? The bus the mesh has and the bus being built spell
+  wildcards differently, and a `consumes` pattern is the one place a module writes one.
+- May a module emit an event named after another module, and if not, what does the module that does
+  it today declare instead?
+- Who replays? A catch-up answer published by the controller under a builder's subject is the
+  controller signing an event as another module, which is the thing the derived namespace prevents.
+  If it must not, then a replay is a different message from an announcement, and the consumer needs
+  to be told so.

04-ISSUES/127-a-module-event-derives-a-subject-nothing-publishes/01-diagnosis.md

@@ -0,0 +1,109 @@
+# Diagnosis — 2026-09-27
+
+## Where it lives
+
+Three places, and only one of them is a bug in code.
+
+**The manifests, in the module catalogue.** Thirty-seven declare events, and every one of them
+spells an event the way a routing key on the bus the mesh runs on today is spelled —
+`module.<module>.<verb>`. [Design 29](../../03-DESIGN/01-to-be/32-what-a-module-declares.md) §1 says
+a module names an event **locally and bare** (`emits: order.placed`) and a consumer names
+`<emitter>.<event>` (`consumes: billing.order.placed`). So the manifests are stale against a rule
+that was already decided, not wrong against an undecided one. **This is the whole of the reported
+symptom.**
+
+**The manifest's own documentation, in the parser.** The comments on `emits` and `consumes` still
+describe the old convention and give the old examples — "dotted topic keys, e.g.
+`module.umami.site.created`", and `"#"` named as the audit logger's pattern. A module author reading
+the file they read most is being told to write the thing that does not work. That is why the drift
+was uniform across thirty-seven manifests rather than scattered: nobody was mistaken, everyone
+followed the documentation.
+
+**Nothing checks either one.** `ParseManifest` validates the module name, the slug, what it provides
+and what it requires. It says nothing about an event name. So a local name that derives to a
+namespace belonging to a module called `module` is accepted by every check the mesh has, and the
+first thing that notices is a subscription that never fires.
+
+## What was ruled out
+
+**The derivation is not wrong.** Asked directly, with the module names and declarations the
+catalogue holds, `PermissionsFor` produces exactly what design 32 §1 specifies for the input it is
+given: it reads a consumer's `<emitter>.<event>` and builds the emitter's subject. Given
+`module.builder.built` it reads the emitter as `module`, which is a correct reading of an incorrect
+declaration.
+
+**The conformance fixtures are not at fault and could not have caught it.** They pin one emitter's
+envelope against one subject, and both halves of that pair are correct. What is wrong is only
+visible when an emitter's derived subject is set beside a *consumer's* derived subject — a
+comparison nothing performs, because until the subject was derived there was nothing to compare.
+
+**Task 3.8's rule is not broken, it is weaker than it reads.** That task asserted **no manifest
+contains a subject**, which holds: a manifest contains a local name. Nothing asserts that a local
+name derives to a subject some emitter actually publishes.
+
+## What is still a decision and not a conversion
+
+Converting the manifests is implementing design 29, not deciding anything. Three of the report's
+open questions are not:
+
+- **Wildcards.** Design 29's table has no wildcard row, and two manifests need one: a module
+  consuming every download completion across several media modules, and an audit logger consuming
+  everything. The two buses spell wildcards differently, and a `consumes` pattern is the one place
+  a module writes one.
+- **A module emitting under another module's name.** One manifest declares an event named for a
+  *provision* rather than for itself. Design 29 §2 makes an event's source a fact the bus enforces,
+  so this cannot survive as written — and the remedy is probably not a rename but a **seat**, which
+  is what a name stable across whoever implements it already is.
+- **Who replays a build announcement.** The controller answers a catalogue's catch-up by
+  re-publishing builds under its *own* name, which no consumer of the builder's subject hears, and
+  for which it holds no grant. Publishing them under the builder's subject would be the controller
+  signing an event as another module — the exact thing the derived namespace prevents. So the
+  catch-up is either a different message or a different mechanism, and that is a decision.
+
+## Owners
+
+`located-in` names the manifests and the parser. The replay question reaches the controller and the
+catalogue module together and is recorded above rather than in that field, because it is not where
+this symptom lives.
+
+# Fixed — 2026-09-27
+
+Converted, and the rule now has checks. What it took was larger than the report said, in two
+directions nobody had looked.
+
+**The module code, not just the manifests.** Forty-three files pass an event name to `emit()` at
+runtime, and the runtime builds the subject from what it is handed. A converted manifest with
+unconverted code would have had the permission and the subject disagree — the same silence, one layer
+down.
+
+**Both clients had to learn the mapping.** Each passed the name straight through, which was right on
+the bus the mesh runs on today only because modules were writing routing keys. So the old bus's client
+now turns a local name into `module.<emitter>.<event>` on the way out and back on the way in.
+**Without that, converting the modules would have broken the mesh that is actually running** — which
+is the opposite of what fixing this was for.
+
+**The declaration and the handler spoke different vocabularies.** The key a module's handler saw was
+the event name alone, while its manifest names `<emitter>.<event>`. So a correct manifest produced a
+pattern that could never match. The subject already carries the emitter; the key names it now.
+
+## The three open questions, answered
+
+- **Wildcards**: `*` is one name, `**` is the rest, spelled the mesh's way and derived to each bus's
+  own. `**` alone is every event, which is what the audit logger wanted and now says in one token.
+- **A module emitting under another's name**: not allowed, and the remedy is the seat rather than a
+  rename — a role's name outlives whoever fills it. **Deferred in practice**: seats carry protocol in
+  the manifest and in the permission model, and the shared library cannot publish on one, so the
+  module that did this emits under its own name and its consumers carry that coupling. Worth a task
+  when a seat's holder needs to emit.
+- **Who replays a build announcement**: still open, and narrowed. It cannot become a reply to the
+  catalogue's inbox: answering a module's inbox needs `_INBOX.>`, which is the blanket grant
+  [design 25](../../03-DESIGN/01-to-be/25-the-bus-on-nats.md) §4 refuses. So the remaining options are
+  a subject the controller may publish and the catalogue may subscribe, or a durable consumer that
+  starts at the beginning of the stream and removes the need to ask at all. Recorded on the work
+  breakdown as the catch-up half of task 4.5 rather than here, because it is no longer this symptom.
+
+## What it found while running
+
+Two dangling subscriptions that predated this and nothing had reported: a module emitting an event its
+manifest never declared, which the new bus refuses outright, and a module waiting for an event nothing
+emits — a demo that could never be triggered, because only that module may publish under its own name.

04-ISSUES/130-undeclaring-a-service-stops-it/00-report.md

@@ -9,7 +9,7 @@ amended-design: 02-DECISIONS/0118-undeclaring-gives-a-unit-back-the-state-it-was
 
 ## What was observed
 
-Reviewing the uplink modules ([ADR 0117](../../02-DECISIONS/0117-a-machines-uplink-is-a-seat.md))
+Reviewing the uplink modules ([ADR 0125](../../02-DECISIONS/0117-a-machines-uplink-is-a-seat.md))
 found that the host's `remove` path stops every `service` resource that is no longer declared:
 `SetServiceState(..., "stopped")`, reported as "stopped; the unit file is not the host's to
 delete". `store.Orphans` matches by id alone. So any of these stops the unit:
@@ -45,7 +45,7 @@ reaches it by.
 
 ## Resolution
 
-[ADR 0118](../../02-DECISIONS/0118-undeclaring-gives-a-unit-back-the-state-it-was-found-in.md):
+[ADR 0126](../../02-DECISIONS/0118-undeclaring-gives-a-unit-back-the-state-it-was-found-in.md):
 undeclaring removes what the mesh made and gives back what it changed. The host records the state
 it first found a unit in, and undeclaring returns the unit to it — a unit found running (the
 container runtime, sshd, a network manager) is left running; one the mesh started (the packet

04-ISSUES/131-nothing-tells-the-mesh-a-source-moved/00-report.md

@@ -0,0 +1,107 @@
+---
+status: resolved
+opened: 2026-09-27
+located-in: [mesh-catalog modules/gitea, mesh-controller cmd/mesh-controller, mesh-controller internal/builder]
+fixed-by: mesh-catalog #124 — the forge module watches for merged pull requests and emits `pull.merged` with the merge commit and the clone address; mesh-controller #110/#111 — the control plane follows that event on the bus, marks every module built from that repository and branch as moved, and builds them bases first, stopping when a base fails; mesh-controller #113/#114 — a build records the bases it was handed and the graph is read from builds, without which "bases first" had no edges to order by.
+amended-design: 03-DESIGN/01-to-be/28-building-the-bus.md
+---
+
+# 131 — Nothing tells the mesh a source moved, and it reports itself current anyway
+
+## What was observed
+
+Six changes were merged to the trunk of six repositories in one sitting. The build machine built
+nothing. Its last build, minutes before the first merge, was still the one it reported; no build was
+requested, refused or failed, because none was ever asked for.
+
+Asked afterwards what was wrong, the mesh said:
+
+> 4 machine(s), all doing what they were told, all heard from, running what the mesh would send them,
+> and every module current with its source
+
+Every one of the six had moved. The last clause was false for all of them, and it is the clause a
+person reads to decide whether there is anything to do.
+
+## Why it matters beyond this instance
+
+**The mesh learns a source moved by being told, and there is no longer anything to tell it.** The
+command exists — a person names the module and the commit — and so does the question the overview
+answers. What is missing is whatever used to connect the two. One repository still carries a forge
+webhook aimed at a port; the rest carry none, and the port belongs to a different service than the
+one the arrangement implies. So the state is not "the trigger is broken" but "there is no trigger,
+and nothing says so".
+
+**A wrong answer is worse here than no answer.** "Every module current with its source" is
+indistinguishable, to a reader, from a mesh that has genuinely caught up. The overview is built to be
+the thing you check instead of checking by hand, so a confident false negative removes the habit that
+would otherwise have caught it. Nothing in the mesh is at fault for being out of date — it is at
+fault for saying it is not.
+
+**It is also why "current with its source" cannot be a stored fact.** The mesh compares what it built
+against what it was last told the source was, and calls that agreement. Two facts agreeing tells you
+nothing when both come from the same place.
+
+## The intended shape, which is decided and not built
+
+The forge emits what happened to it — a pull request merged — and the build machine reacts by
+building what that commit affects. That keeps the forge ignorant of the build system and the build
+machine ignorant of the forge's internals, which is the same argument
+[ADR 0126](../../02-DECISIONS/0126-a-module-declares-its-own-seats.md) makes for addressing an event
+to its emitter: the merge is a fact about the forge, and what should be rebuilt because of it is not
+the forge's business to know.
+
+The forge's module already declares the event. The build machine declares that it consumes nothing.
+
+## What the trigger cannot be
+
+**Not one build per changed module.** The modules form a graph: several are built from one
+repository, and some are the base another is compiled on — a runtime image, a compiler base, a
+repository whose context a second module builds from. Firing a build for each changed module
+independently would start work that cannot succeed yet and produce a failure per dependent, for one
+cause.
+
+Observed while catching the mesh up by hand on 2026-09-27: a compiler base had to move before
+anything compiled against it could build, and when it failed, the right behaviour was for its
+dependents to wait rather than each fail the same way. Fifteen modules shared the cause. A trigger
+that reports it fifteen times has buried it.
+
+So whatever reacts to the forge's event resolves what changed into an order, builds the bases first,
+and holds a dependent while its base is unbuilt or failed. That is a larger thing than "rebuild what
+the commit touched", and knowing it now is cheaper than discovering it from fifteen identical
+failures.
+
+## Open questions
+
+- Is "the source moved" still a thing a person can assert by hand once the event path exists, or does
+  the hand-operated form become the thing that made this failure possible?
+- Which commit does the build machine act on — the merge, or each commit it brought — and what does
+  it do when several arrive for one module at once?
+- How does the overview stop being able to lie? Comparing what was built against what was recorded
+  will always agree. Whether the trunk has moved is a question only the forge can answer, so either
+  the overview asks it, or it stops claiming to know.
+- Does this want to be the same mechanism as the build request on the bus
+  ([ADR 0129](../../02-DECISIONS/0129-a-seat-carries-the-protocol-of-its-role.md)), or does it sit in
+  front of it?
+
+## What was done (2026-09-28)
+
+The shape above was built as described: the forge's module emits the merge, the control plane
+consumes it, and nothing on either side knows the other's internals. The build is asked for the
+merge commit, not each commit the merge brought — the trunk moved once, to one place. Several merges
+for one module arriving in a row are followed in turn, each moving the recorded source to its own
+commit, so the last one to arrive is the one the mesh ends up built from.
+
+The hand-operated form stays. `module moved` is how a source is recorded without a forge — a module
+built from a repository elsewhere, or a mesh whose forge module is down — and it is the same act the
+event performs, so the two cannot disagree about what "moved" means.
+
+**Bases first needed edges, and there were none.** The order this report asked for was written and
+walked a graph that no build had ever recorded: a recipe reads its base from a build argument, so the
+digest was never in the file the builder read edges from. A build now reports what it was handed, the
+control plane records it by artifact path, and the order is read from each module's newest build.
+
+**What still can lie.** The overview compares what was built against where it was last told the
+source is; the forge's event is now what moves that mark, so it is right for as long as the forge
+module was listening. A merge made while that module was down is a merge the mesh does not know of
+until the module next polls — it announces what merged since it last looked, so the gap closes when
+it comes back, and not before. The overview does not say so.

04-ISSUES/132-a-module-can-be-recorded-without-the-directory-it-lives-in/00-report.md

@@ -0,0 +1,60 @@
+---
+status: resolved
+opened: 2026-09-28
+located-in: [mesh-controller cmd/mesh-controller]
+fixed-by: mesh-controller — `module add` takes `--path` and `--self`, so a module handed over by hand records the whole location it came from; a record naming a repository and no directory says so in the reply; the rule is one function with a test beside it. The nine records already wrong were corrected by rebuilding each with its real directory, which is the same act through the same door.
+amended-design:
+---
+
+# 132 — A module can be recorded without the directory it lives in
+
+## What was observed
+
+Nine modules on one mesh could not be rebuilt. Each attempt failed the same way:
+
+> has no module.json at its root, so there is nothing saying what it is
+
+All nine were recorded as coming from a repository that holds many modules, each in its own
+directory — and each record named the repository and no directory. So every build cloned the
+repository and looked for a manifest where there has never been one.
+
+The failure only surfaced when something asked for all of them at once. Before that, the overview
+said every module was current with its source, because what it compares is what was built against
+what the mesh was last told the source has, and neither half knows whether the source can be found
+at all.
+
+## Why it matters beyond this instance
+
+**A module is a repository and a directory inside it** ([ADR 0069](../../02-DECISIONS/0069-a-module-is-a-repository-and-a-path.md)),
+and one of the two doors into the catalogue could record only the first half. A build records the
+directory it was given, so a module that arrived by being built is always whole; a module handed over
+by hand had no way to say where it lived, and the flag to say it did not exist. The rule was decided
+and enforced on one path out of two.
+
+**Half a location reads exactly like a whole one.** Nothing in the record is empty in a way a person
+would notice: the repository is there, the branch is there, the commit is there. The mesh only finds
+out at the moment it needs the manifest, which is the moment it is trying to rebuild — and the module
+stays on whatever it last built, indefinitely, with nothing saying why.
+
+**It is the same shape as [131](../131-nothing-tells-the-mesh-a-source-moved/00-report.md).** A
+comparison between two facts the mesh holds about itself will agree with itself. Whether the source
+can be found is a question only an attempt to read it answers, and the answer had nowhere to go.
+
+## What was done
+
+`module add` takes the directory and which forge holds the repository, so a hand-registered module
+records the same whole location a built one does. What a record must say to be worth anything is one
+function with a test beside it, rather than a paragraph in a help string: provenance together or not
+at all, a directory needs a repository to be inside, a path on the mesh's own forge is not an address.
+And a record that names a repository but no directory says so when it is made — not refused, because a
+module really at a repository's root is ordinary, but said, because the person adding it is the one
+who knows which it is.
+
+The nine wrong records were corrected by building each with its real directory, which re-records it.
+No row was written by hand.
+
+## What is still true
+
+A directory that does not exist in the repository cannot be refused when the module is added: the
+control plane does not clone, and inventing a check there would mean it did. The first build says so
+plainly, which is one build rather than nine, and the record it leaves behind is right from then on.

04-ISSUES/133-the-control-planes-schema-is-migrated-at-birth-and-never-again/00-report.md

@@ -0,0 +1,78 @@
+---
+status: resolved
+opened: 2026-09-28
+located-in: [mesh-controller module.json]
+fixed-by: mesh-controller — the control plane's module declares a run-once `migrate` step before its server, which is the shape ADR 0052 prescribes for exactly this. A step's record of having run is the digest of its declaration and the image is part of that digest, so a new build of the control plane re-runs it; and because a run-once step gates what the declaration places after it, a migration that fails stops the new server from starting at all rather than letting it run against a schema it does not have.
+amended-design: 03-DESIGN/01-to-be/32-what-a-module-declares.md
+---
+
+# 133 — The control plane's schema is migrated at birth and never again
+
+## What was observed
+
+On 2026-09-28 at 08:17 the control plane was replaced, by the mesh's own upgrade path, with a build
+whose code writes a column that a migration **in that same build** creates. Nothing ran the migration.
+
+For the next three quarters of an hour the mesh built things and recorded none of them. Every build
+answered:
+
+> ERROR: column "built_contexts" of relation "build" does not exist (SQLSTATE 42703)
+
+and that sentence went only to whoever happened to be waiting on a build's reply. The overview kept
+saying the mesh was fine. The builds themselves worked — images were built and published — so the
+registry filled up with artifacts the mesh has no record of, and the graph stopped learning without
+anything saying so.
+
+The schema was created once, at genesis, by an action in the foundation bundle that runs the same
+binary's `migrate`. Nothing runs it again. The mesh has updated its own control plane many times since
+that bundle, and every one of those updates carried whatever migrations the new build brought and
+applied none of them. This is the first time a build needed one.
+
+## Why it matters beyond this instance
+
+**The schema and the code that needs it ship as one artifact and are applied by two mechanisms, only
+one of which is automatic.** A module's version is atomic everywhere else in the mesh — the manifest,
+the image and what the machine runs move together. Its schema did not, so "the mesh updates itself on
+a push" was true of the code and false of what the code needs.
+
+**The failure is quiet exactly where quiet is worst.** A build that cannot be recorded is a build that
+happened and left no trace, which is the fault [issue 050](../050-the-catalogue-knows-nothing-built-before-it/00-report.md)
+and [issue 131](../131-nothing-tells-the-mesh-a-source-moved/00-report.md) are both about. The mesh
+has three mechanisms for noticing a module is behind its source and none for noticing that what it
+recorded was refused.
+
+**The shape was already decided, and the control plane was the one module that did not use it.**
+[ADR 0052](../../02-DECISIONS/0052-a-step-that-runs-once-before-a-container.md) says a run-once container is a
+step the host runs to completion before whatever the declaration places after it, and names migrating
+a schema as the case it exists for. The genesis code's own comment says a manifest may name its image
+in more than one resource — "a migrate step beside the server". The control plane's manifest had no
+such step; it went straight from a state directory to the server.
+
+## What is still true
+
+**Additive migrations are load-bearing, not a style preference.** The step runs before the *new*
+server starts, which means the old binary briefly runs against the new schema. A migration that
+removes or renames something would break the running control plane in the window between the two.
+
+**A hand-written step is one the next module forgets**, which is why this fix is not where the matter
+ends: [ADR 0135](../../02-DECISIONS/0135-a-module-version-prepares-its-state-before-it-runs.md) makes it
+derived and puts it where an author works: a module version declares an entrypoint that prepares its
+state, and the mesh composes the gated work from it, so the control plane stops being the only module
+that had to remember. That record also settles the level question HAL answered with stages — a consumer
+is a module on a machine, so the scope of preparation is the scope of the state — and
+[ADR 0134](../../02-DECISIONS/0134-the-mesh-says-what-it-applied.md) answers the second open question
+below: what a machine applied, and what it refused, become facts on the bus rather than a line in a log.
+
+**The mesh now has two shapes for one problem.** The catalogue module migrates its own schema in its
+own code when it starts; the control plane migrates in a step the host gates on. Both work and the
+reasons differ — a module that owns its store entirely can do it at start, while a step is visible in
+the declaration and refuses to let a broken upgrade serve. Which one the mesh should standardise on is
+a decision, not a fix, and it is not made here.
+
+## Open questions
+
+- Should a module be refusable at registration when it ships migrations and declares no step and no
+  other way to apply them? The mesh can see both halves.
+- Should a record the store refuses reach the overview? Today the only reader of that failure is
+  whoever asked for the thing that failed, and for an event arriving on the bus there is no such
+  person.

04-ISSUES/134-a-definition-may-still-name-the-mesh/00-report.md

@@ -0,0 +1,66 @@
+---
+status: open
+opened: 2026-09-28
+located-in: [mesh-catalog, mesh-controller internal/catalogue]
+fixed-by:
+amended-design:
+---
+
+# 134 — A definition may still name the mesh, and the check that would say so does not exist
+
+## What was observed
+
+[ADR 0112](../../02-DECISIONS/0112-a-module-definition-names-no-node-mesh-or-path.md) says a module
+definition names no node, no mesh and no host path, and states how that is checked:
+
+> A catalogue test finds no domain name in any definition value.
+
+There is no such test. Run by hand on 2026-09-28, across the 72 manifests in the catalogue, the
+question it asks has 15 answers. They are not all the same kind of thing, and the difference matters
+more than the count:
+
+**Values the mesh acts on** — seven:
+
+| module | where | what it names |
+|---|---|---|
+| keycloak | `env.KC_HOSTNAME` | this installation's public name for itself |
+| minio | `env.MINIO_BROWSER_REDIRECT_URL` | the same, for its console |
+| invoicing | a resource's `image` | a named registry rather than the mesh's artifact store |
+| builder | `build.artifacts[].context.repository` | the forge, by URL |
+| route-proxy | `build.artifacts[].context.repository` | the forge, by URL |
+| route-adapter | a resource's `content` | a proxy's dynamic configuration |
+| novox.be | `module` | the module is named after the domain it serves |
+
+**Prose** — eight, in `listens[].why`: de-spiegel, mailu, n8n, only-office, photos, photos-eef,
+photos-filip, portainer. Each explains what a port is for and mentions the public name it is reached
+by. Nothing reads these; a check written as a string search would report them, and reporting them as
+violations of the same rule would be wrong.
+
+## Why it matters beyond this instance
+
+**An unenforced rule is indistinguishable from a wrong one, and costs more, because people believe
+it.** The record says the mesh is name-agnostic, four design documents rest on that, and a reader
+checking whether it holds finds that it does not — in the places that matter most. The two forge URLs
+are what a build reaches into for its source; the two hostnames are what a service tells a browser
+about itself.
+
+**It is the difference between a mesh and this mesh.** A definition carrying `novox.be` is a
+definition that can only be installed here. The whole point of the rule is that the same catalogue
+raises a different mesh with a different name, and today seven modules would need editing to do it.
+
+**And the shape of the fix is not the same for each.** A public name is an operator's choice about an
+assignment, which ADR 0112 already provides for; a forge URL should be a path on the git seat
+([ADR 0111](../../02-DECISIONS/0111-a-build-source-is-on-the-git-seat-or-external.md)); an image from a named
+registry is a question about the artifact store, not about naming. Counting them together would hide
+that.
+
+## Open questions
+
+- Does a domain in a `why` string break the rule? It is documentation the mesh never reads, and a
+  check that cannot tell the two apart will either pass things it should catch or fail things nobody
+  should change.
+- Where does a service's public name live, concretely — a setting on the assignment, or a fact the
+  mesh composes from the node's domain? ADR 0112 says a requirement the mesh resolves; the two
+  hostnames above are the first real cases.
+- Should a build context name a repository on the git seat rather than by URL, and if so, what does
+  that mean for a context in *another* mesh's forge?

04-ISSUES/135-a-containers-mesh-names-are-not-compared/00-report.md

@@ -0,0 +1,70 @@
+---
+status: resolved
+opened: 2026-09-28
+located-in: [mesh-host internal/apply]
+fixed-by: mesh-host — a container's mesh names are part of the spec digest the host compares, sorted so the digest does not move for a reordering. A container whose names moved is now recreated like a container whose image moved, and the test fails against the previous behaviour.
+amended-design:
+---
+
+# 135 — A container's mesh names are not compared, so a moved address is never noticed
+
+## What was observed
+
+One container on this mesh had been restarting every thirty seconds for five days — 2286 times — and
+the mesh reported the machine as doing what it was told.
+
+Its logs said its database connected and then a query timed out. The database was reachable: the same
+query from the same network, with the same credential, answered in milliseconds. What differed was the
+name. Inside that container, `novox.internal` resolved to `10.42.0.1`; in every other container on the
+machine it resolved to `10.10.0.1`. The mesh's overlay range had moved, and this container still held
+the old one:
+
+```
+umami          created 2026-09-23   novox.internal:10.42.0.1
+mesh-catalog   created today        novox.internal:10.10.0.1
+```
+
+A container resolves other machines and public names through the entries the mesh gives it when it is
+created, and nothing re-reads them afterwards. The host compares a container against what was declared
+by a digest of its spec — image, name, environment, ports, volumes, arguments, resolver, address, and
+what it reads — and **the mesh's names were not in it**. So this container matched what was declared,
+was left alone, and kept an address that had not existed for five days.
+
+Forty-eight other containers had current names. Not because anything corrected them: each had been
+recreated for some other reason — a new image, a changed file — and picked up the current roster on the
+way. This one's image is an upstream release that had not moved, and nothing else about it changed, so
+nothing ever recreated it.
+
+## Why it matters beyond this instance
+
+**It is the exact fault [issue 045](../045-a-container-keeps-the-values-it-started-with/00-report.md)
+named, in the one field that was left out.** That issue is why the digest carries what a container
+reads: "a container whose configuration had since been rewritten compared equal and was left alone —
+running values the machine no longer holds, while every check reported success." The same sentence
+describes this, with *names* in place of *files*.
+
+**The failure is invisible in exactly the way that matters.** The container runs, so the machine
+reports it applied. It restarts, but a restarting container is a normal sight during an upgrade. The
+only account of the fault is inside the container's own log, in the words of the application rather
+than of the mesh — and what it says is that a query timed out, which points at the database.
+
+**And it is most likely to bite what changes least.** Every container that is rebuilt often repairs
+itself by accident. The victim is the module whose image is stable — which is to say, the module that
+was working fine.
+
+## What was done
+
+The mesh's names are part of the digest, sorted so the digest does not move for a reordering nobody
+made. A container whose names moved is now recreated exactly as one whose image moved.
+
+The first apply after this recreates every container that carries mesh names — one restart each,
+already the price the mesh pays for any image update — because their recorded digests predate the
+field.
+
+## What is still true
+
+The mesh gives a container its names at creation and has no way to change them in place. That is the
+container runtime's shape, not a choice; the answer is to recreate, which is what this does. A module
+that would rather re-read a roster from a file can already ask for one as a fact
+([ADR 0120](../../02-DECISIONS/0120-a-roster-fact-carries-its-format-as-a-template.md)) and restart on
+it.

04-ISSUES/136-a-module-may-name-a-program-the-machine-does-not-have/00-report.md

@@ -0,0 +1,92 @@
+---
+status: resolved
+opened: 2026-09-28
+located-in: [mesh-catalog modules/fail2ban]
+fixed-by: mesh-catalog — the intrusion-prevention module bans through an action it ships itself, already in use on every machine, instead of naming a firewall front-end two of them do not have. The instance is closed; the class in "What is still true" is not.
+amended-design:
+---
+
+# 136 — A module may name a program the machine does not have, and everything reports success
+
+## What was observed
+
+Two machines were given the intrusion-prevention module on 2026-09-28. Both refused to start it:
+
+```
+ERROR Failed during configuration: Have not found any log file for 'recidive' jail.
+ERROR Async configuration of server failed
+fail2ban.service: Main process exited, code=exited, status=255/EXCEPTION
+```
+
+The jail that bans whoever keeps coming back reads the service's *own* log, and the service checks
+every jail's log file while it configures itself — before it has created that log. The module
+declared the jail and shipped the rotation for that log, and never declared the log. On the two
+machines where it had run for years the file was simply there, so nothing had ever noticed.
+
+That failure was loud. Fixing it uncovered a second one in the same module that is not.
+
+The module's defaults named `ufw` as the way to ban an address. Two of these four machines have no
+`ufw` — they filter with nftables — and nothing checks that until an address is banned. Asked to ban
+a documentation address on such a machine, the service accepted the instruction, counted it, ran the
+command, and wrote this to a log nobody reads:
+
+```
+ERROR   ... -- stderr: '/bin/sh: line 5: ufw: command not found'
+ERROR   ... -- returned 127
+ERROR   Failed to execute ban jail 'sshd' action 'ufw' ... Error banning 192.0.2.99
+```
+
+No rule existed afterwards. Throughout, the unit was `active`, the module was applied, and the
+machine's report said so. **A machine had been added to the mesh's intrusion prevention, reported as
+protected, and was banning nobody.**
+
+## Why it matters beyond this instance
+
+**The two faults are the same mistake with opposite symptoms.** Both are the module assuming
+something about the machine — a file that happens to exist, a program that happens to be installed.
+One stopped the service, which anybody notices. The other left it running and empty, which nobody
+does. A mesh that only catches the loud one is a mesh whose coverage is unknown.
+
+**"The unit is running" was taken for "the module is doing its job".** That is the only health a
+service resource has. It is the right answer for most modules and it is silent for any module whose
+work happens later, on an event — a ban, a renewal, a backup, a notification. The report cannot
+distinguish "protecting this machine" from "installed and inert".
+
+**And it is exactly the naming rule, one level down.**
+[ADR 0112](../../02-DECISIONS/0112-a-module-definition-names-no-node-mesh-or-path.md) says a
+definition names no node, no mesh and no host path, because the same definition has to raise a
+different mesh. `ufw` is not a node name, but it is the same class of assumption: a value the module
+cannot know, true on some machines and false on others, written as though it were a constant. The
+module already knew how to do better a few lines away — the mesh's own address range is named there
+as something the machine fills in.
+
+## What was done
+
+The module declares the log its own jail reads, created once and never touched again, since what
+grows in it is the service's and the rotation the module already ships is what keeps it small. And
+it bans through the action it ships itself, which every machine here can run, which was already in
+use by the other jail on all four, and which covers a container's published port as well as the
+host's own.
+
+All four machines now run it, with both jails, and a ban lands on each — verified by banning and
+unbanning a documentation address on every one.
+
+## What is still true
+
+**Nothing would have caught either fault before it shipped.** The control plane reads a manifest, not
+a machine; `ufw` and `/var/log/…` are strings in a file it has no way to evaluate. The host could in
+principle be asked whether a declared program exists, but no resource says "this file names a command
+that must be there", so there is nothing to check.
+
+**Two machines' bans from before this are stale rules in the old front-end**, which the service no
+longer knows about and will never lift. They reject two addresses for ever. Harmless, and a reminder
+that changing how a module enforces something leaves what it already enforced behind.
+
+## Open questions
+
+- What does a service resource's health mean for a module whose work is event-driven? A unit being
+  active is the weakest claim available, and four of this mesh's modules are of that kind.
+- Should a declaration be able to say that a resource depends on a program, so the machine can refuse
+  what it cannot carry out rather than reporting success?
+- Where should the packet filter a module bans through come from — the module's own choice, as now,
+  or the seat that owns the machine's filtering?

04-ISSUES/137-converging-a-machine-cut-off-its-own-guests/00-report.md

@@ -0,0 +1,74 @@
+---
+status: resolved
+opened: 2026-09-28
+located-in: [mesh-controller internal/catalogue]
+fixed-by: mesh-controller — a machine says which networks it routes and the derived filter forwards them, their guests keeping address and name service ([ADR 0137](../../02-DECISIONS/0137-a-machine-says-which-networks-it-routes.md)).
+amended-design:
+---
+
+# 137 — Converging a machine cut off its own guests, and nothing said so
+
+## What was observed
+
+A workstation was flipped from adopted to converged, so the mesh's derived filter replaced what was
+there. The flip reported success, the machine reported that it had applied its declaration, and every
+surface of the mesh read green.
+
+A container on one of that machine's networks could no longer reach anything:
+
+```
+192.168.64.2/20
+OUTBOUND BLOCKED
+```
+
+Five of the machine's container networks were affected, and every network its test beds create. The
+reason is in the filter's forward chain, which denies by default and then allows two ranges:
+
+```
+ip saddr 172.16.0.0/12 accept   # the container runtime's bridge networks
+ip saddr 192.168.128.0/17 accept # the networks its compose files are given
+```
+
+Those two are constants in the controller. The machine's guests were allocated from neither: its
+compose networks from other parts of `192.168/16`, and each test bed a fresh `10.x/24`. So the rules
+were correct for a machine whose runtime was left at its defaults, and a guess on this one.
+
+Two further things were closed by the same flip, and for the same reason nobody saw them: a guest asks
+its host for an address over DHCP and for names over DNS, both of which arrive at the input chain,
+where no module had declared them.
+
+## Why it matters beyond this instance
+
+**The preview could not have warned.** It lists what the machine reported as *listening*, and says so
+honestly: it ends with a line that traffic the machine routes is "not previewed". What it did not say
+is that routing was about to be denied by default, or which ranges would survive. An operator reading
+a 350-line preview approves what it shows.
+
+**It is the second time today that a constant stood in for something the mesh cannot know.** The
+intrusion-prevention module named a firewall front-end two machines do not have
+([issue 136](../136-a-module-may-name-a-program-the-machine-does-not-have/00-report.md)), and the
+filter names the address ranges one runtime happens to use. Both were true where they were written and
+silently false elsewhere.
+
+**And the code already knew.** The comment above those two lines says a machine configured otherwise
+"needs this to say so — which is a thing the mesh cannot derive and a reason this list is named here
+rather than computed". The gap was documented at the point where it was introduced, and the way to say
+it was never built. A comment naming a missing mechanism is a rule that is not enforced.
+
+## What was done
+
+A machine says which networks it routes; the filter forwards them and admits their guests' address and
+name service. Added to the runtime's defaults rather than replacing them, so a machine that names one
+range keeps the others. Node-level, because the machine routes them and the module that loads the
+filter may be replaced. The converge preview now says what a machine routes, and what it will keep
+forwarding if it says nothing.
+
+## What is still true
+
+**The flip is still the moment a machine's unmanaged services close.** That is what converging means
+and the preview names each one. This issue is not about the ports that were meant to close; it is about
+the ones nothing could name.
+
+**Egress is still not previewed per network.** The preview says which ranges will be forwarded, not
+which of the machine's guests sit inside them. Deriving that would need the machine to report its
+bridges, and a bed's bridge does not exist until the bed runs.

04-ISSUES/138-two-modules-claim-one-seat-and-are-not-interchangeable/00-report.md

@@ -0,0 +1,56 @@
+---
+status: open
+opened: 2026-09-28
+located-in: [mesh-controller internal/catalogue, mesh-catalog]
+fixed-by:
+amended-design:
+---
+
+# 138 — Two modules claim one seat and are not interchangeable, and nothing says so
+
+## What was observed
+
+Three modules claim the node-scoped uplink seat: one for each network manager a machine here might
+run. [ADR 0117](../../02-DECISIONS/0117-a-machines-uplink-is-a-seat.md) gives each of them the same
+job — ask the manager the machine already runs to leave the resolver file alone and to leave the mesh's
+interface alone — and deliberately keeps the machine's own links out of the mesh's hands.
+
+A seat means one holder and an interchangeable holder. These are interchangeable in what they *ask*
+and not in what they *do*:
+
+- None installs, enables, starts or stops the manager. That is on purpose: stopping it takes every
+  link down, including the mesh's own way in.
+- None carries an address, a route or a wireless credential, for the same reason.
+- **Nothing checks that the module holding the seat names the manager the machine is actually
+  running.** Assigning the systemd-networkd holder to a machine running NetworkManager writes a file
+  for a daemon that is inactive and disabled, the seat reports held, and the two things the seat
+  exists to arrange are arranged for nobody. NetworkManager goes back to rewriting the resolver file
+  on every lease, which is the failure the module's own comment describes.
+
+The machine reports which service manager and which units are active, so the fact needed to catch this
+is already in the report the mesh holds.
+
+## Why it matters beyond this instance
+
+**A seat is the mesh's promise that a role is filled.** If the holder can be a module for software
+that is not running, the seat says a role is filled while nothing fills it — and the surface that
+would tell an operator says "held".
+
+**It is the same shape as two faults found the same day.** A module named a firewall front-end the
+machine does not have ([issue 136](../136-a-module-may-name-a-program-the-machine-does-not-have/00-report.md)),
+and the filter named address ranges one runtime happens to use
+([issue 137](../137-converging-a-machine-cut-off-its-own-guests/00-report.md)). Each is a claim about
+the machine that nothing on the machine checks.
+
+**And it decides whether the seat is worth having.** Either the holder must match what the machine
+runs, which is a condition the mesh can check from the report it already has, or the holders must be
+able to switch the manager, which ADR 0117 refuses for a reason that has not changed.
+
+## Open questions
+
+- Should a seat's conditions of holding include a capability the machine reports, so a holder naming
+  absent or inactive software is refused rather than recorded?
+- Is "the uplink" one seat at all, if its holders are three dialects of the same two requests? The
+  alternative is one module that speaks whichever dialect the machine needs, chosen from the report.
+- What should happen on a machine that switches manager afterwards? The seat would then be held by the
+  wrong module, and the machine is the only place that knows.

04-ISSUES/139-an-internal-route-name-resolves-to-the-consumers-node/00-report.md

@@ -0,0 +1,51 @@
+---
+status: open
+opened: 2026-09-28
+located-in: [mesh-controller internal/catalogue]
+fixed-by:
+amended-design:
+---
+
+# 139 — An internal route name resolves to the consumer's node, not the one that serves it
+
+## What was observed
+
+A module that requires a route is given two names: a public one composed under the serving node's
+domain, and an internal one composed under the consumer's own machine — `<label>.<node>.internal`.
+
+The two are published differently:
+
+- The **public** name is written into every machine's hosts file at the address of the node whose
+  proxy answers it. The mesh computes that deliberately, so any container resolving a routed name
+  reaches the proxy.
+- The **internal** name is resolved by the machine's own resolver, which answers every name under
+  `<node>.internal` with that node's address — the consumer's, because the name was composed from it.
+
+Where the proxy runs beside the consumer these are the same machine, which is every case on this mesh
+today, and both names work. Measured on 2026-09-28: the internal name of a service on the control node
+answers with a certificate from the mesh's internal authority, and the public name with one from the
+public authority.
+
+Where the proxy is on another machine they disagree. The internal name sends the client to a machine
+that runs no proxy and has nothing listening on the port, while the public name sends it to the one
+that does.
+
+## Why it matters beyond this instance
+
+**It is latent exactly where the mesh is heading.** `route` is provided mesh-wide precisely so a
+module can be routed by a proxy on another machine. The first module assigned that way gets an
+internal name that does not work, and the public one that does — with no error anywhere, because both
+names resolve.
+
+**A per-machine name is what an operator will reach for.** `<service>.<machine>.internal` reads like a
+promise that the service on that machine is reachable there, and the wildcard makes every such name
+resolve whether or not anything answers.
+
+## Open questions
+
+- Should the internal name be composed under the serving node, like the public one, or should it stay
+  the consumer's and be published at the serving node's address like the public name is?
+- Is a per-node route holder the real answer — a proxy on every machine that serves its own names —
+  and if so, is `route` still one mesh-wide provision or a node-scoped seat with a mesh-wide fallback?
+- What certifies the name in either case? The certificate is obtained by whoever terminates TLS, and
+  that is the question above in another form.

04-ISSUES/140-an-endpoints-reach-is-not-declared/00-report.md

@@ -0,0 +1,79 @@
+---
+status: located
+opened: 2026-09-28
+located-in:
+  - mesh-controller internal/catalogue/manifest.go
+  - mesh-controller internal/catalogue/filtering.go
+  - mesh-controller internal/catalogue/declaration.go
+  - mesh-controller examples/route-proxy
+  - mesh-catalog (every routed module manifest)
+fixed-by:
+amended-design: 03-DESIGN/01-to-be/08-connectivity.md
+---
+
+# 140 — An endpoint's reach is not declared, so three mechanisms each decide it separately
+
+## What was observed
+
+Preparing to converge the mesh's control-node — the last machine still running the firewall it
+had before the mesh — the question came up for one module: the forge serves git over ssh, and that
+port must stay reachable from outside the private network. Where is that said?
+
+The manifest declares the port with a source of `mesh`, so the derived filter would close it to
+everything but the private network. Looking for the place an assignment says otherwise, there are
+two per-node settings keys: one that gives a module's declared port a machine port, and one that
+overrides a declared port's source. The second has exactly one caller — the function that builds
+the node's filter rules. Nothing else in the control plane reads it.
+
+A module's routed endpoint is declared somewhere else entirely: a route contribution naming a label
+and a port. It says nothing about reach. The proxy composes a **public** name and an **internal**
+name for every route it is given, and obtains a certificate for each from a different authority.
+Measured on that machine the same day: an identity provider's public name signed by the public
+authority for 90 days, its internal name signed by the mesh's own intermediate for 24 hours and
+renewed daily. Both names exist, and both certificates, because the proxy makes every name it can.
+No assignment asked for either.
+
+So the forge's ssh endpoint has a firewall source and nothing else — no name, no certificate, and no
+way to say it should be public other than a key the filter alone reads. And the forge's web endpoint
+has two names and two certificates that nobody requested.
+
+## Why it matters beyond this instance
+
+**Reach is stated twice, in two vocabularies, in two places that cannot disagree out loud.** A port
+may be exposed to anywhere while the module contributes no public route; a public route may be served
+for a module whose own listen is private. Nothing reconciles the pair or refuses it. Each mechanism
+is separately defensible and the combination is unstated.
+
+**The vocabulary belongs to the filter, not to reachability.** *Public, internal, or both* cannot be
+expressed. A source of `anywhere` is one rule on one chain; it says nothing about which names should
+exist or which authority should sign them. So "this endpoint must not be public" has no way to be
+written, and is therefore enforced by nothing — while a public certificate for that very name is
+obtained automatically.
+
+**An endpoint is not a thing in the model.** A module has ports, and separately it has routes.
+Nothing binds a port to a name to a certificate, which is why three mechanisms each decide reach on
+their own and none of them is wrong. This is
+[ADR 0045](../../02-DECISIONS/0045-a-machine-firewall-is-the-sum-of-what-it-listens-on.md)'s fault
+one level up: that record closed "a declaration that reads as a restriction and restricts nothing"
+for the packet filter. Here the declaration is absent altogether and the mechanisms guess.
+
+**It blocks the certificate work.** The open question recorded for certificates — a name that must
+not be public needs either DNS-01 or the internal authority only — cannot be answered while no
+assignment states whether a name should be public. Neither can expiry reporting, revocation, or what
+happens to a name when a machine leaves: all of them need to know which names were *meant*.
+
+## Open questions
+
+- Should an assignment name each of a module's endpoints, bind it to a node-level port, and state
+  whether it is reachable publicly, internally or both — with the filter, the proxy's names and the
+  certificate authority all derived from that one statement?
+- What is an endpoint that is neither routed nor certified? Git over ssh is public reach with no name
+  and no certificate; the model has to hold that without inventing one.
+- Are the two existing settings keys the same statement, half-built? If so, is this a new declaration
+  or the completion of theirs?
+- Does an internal-only endpoint get a certificate at all, and from which authority — and does that
+  settle [issue 129](../129-nothing-makes-a-machine-trust-the-meshs-authority/00-report.md), where nothing
+  installs the mesh's own root?
+- Does declaring reach per assignment also settle
+  [issue 139](../139-an-internal-route-name-resolves-to-the-consumers-node/00-report.md), where an
+  internal name resolves to the consumer's machine instead of the one serving the endpoint?

04-ISSUES/141-the-forward-chain-does-not-follow-the-modules/00-report.md

@@ -0,0 +1,88 @@
+---
+status: located
+opened: 2026-09-28
+located-in:
+  - mesh-controller internal/catalogue/filtering.go
+  - mesh-host internal/apply
+fixed-by:
+amended-design: 03-DESIGN/01-to-be/08-connectivity.md
+---
+
+# 141 — The forward chain does not follow the modules, though the modules declare their networks
+
+## What was observed
+
+[ADR 0137](../../02-DECISIONS/0137-a-machine-says-which-networks-it-routes.md), decided the same
+week, gave a machine a way to say which networks it routes for its guests, because the derived
+filter's forward chain had until then allowed two ranges named as constants in the control plane's
+own source — the container runtime's default bridge pool, and half of the pool its compose files
+are given.
+
+Checking the last machine still to be converged, the same fault was found to be live there, and the
+declaration needed to work around it turned out to be wrong in kind.
+
+That machine hosts twenty-one container networks. Nine fall inside the runtime's bridge pool and
+are forwarded. Twelve sit in the other private range, and **six of those fall below the lower bound
+of the constant**, so the flip would have cut their guests off exactly as it did on the workstation
+that produced 0137.
+
+Naming a range to cover the six was the obvious move, and is what 0137 provides for. But of those
+six networks, **four are networks the mesh's own modules declare** — they appear as network
+resources in the node's plan, created by the host because a module asked for them — and **two are
+leftovers of the predecessor**, compose networks of services the mesh does not run. A range wide
+enough to keep the four would have forwarded the two as well: a firewall widened by hand to protect
+networks that should not exist.
+
+The mesh already knows which of the twenty-one are its own. It made them.
+
+## Why it matters beyond this instance
+
+**The node's configuration is supposed to follow the modules assigned to it.** That is the mesh's
+founding shape — the machine runs modules, and its files, its filter and its accounts are composed
+from what runs there. The forward chain is the one derived thing that does not: it consults two
+constants and, since 0137, a list a person types. A module added tomorrow brings a network the filter
+will not forward; a module deprecated leaves a range in the list that outlives it.
+
+**A typed range cannot distinguish the mesh's networks from what was left behind.** It is stated in
+addresses, and addresses are what the runtime allocates, so the only honest declaration is one wide
+enough to include whatever else the runtime has handed out. The derivation is narrower than anything
+a person can safely write, because it names networks rather than ranges.
+
+**0137 rejected deriving this, and was right about what it rejected.** It considered deriving the
+list from *what the machine reports* and refused, on two grounds: a test bed creates its bridge
+between one declaration and the next, and a filter that follows whatever appeared on the machine is a
+firewall that widens itself. Deriving from the **declaration** is neither. The set is known before
+the network exists, because a module declared it; and it cannot widen itself, because only a network
+some module asked for is ever forwarded. What remains genuinely for a machine to say is guests no
+module declares — a test bed's pool — which is a much smaller residue than the list as it stands.
+
+**The gap is invisible in the one place that should show it.** The converge preview lists what
+*listens*, and routing is not a listener. It says in one line what the machine routes, and a reader
+has to know the runtime's allocations to tell whether that line is sufficient. On the machine
+measured here it read as though nothing needed saying.
+
+## What was decided
+
+*2026-09-28, later the same day.* The answer is not a better list. The question in the first open
+item below — should the chain be derived from the networks the modules declare — was answered *no*,
+after a converged machine's rendered rules were read: the chain blocks everything passing through the
+machine and then allows its own guests back by listing their addresses. Every route to a correct list
+fails, because the mesh has no position on a container reaching outward in the first place. The filter
+now constrains what arrives from **outside** the machine and says nothing about what did not, and a
+machine says which of its links face outside — one reported fact instead of a list. See
+[ADR 0140](../../02-DECISIONS/0140-the-filter-constrains-what-arrives-from-outside.md), which
+supersedes both 0137 and the first attempt at answering this.
+
+## Open questions
+
+- Should the forward chain be derived from the network resources the node's modules declare, with the
+  host resolving each declared network to its address the way it already resolves a container by name?
+  The controller cannot render the address itself: a module's network resource carries a name, and the
+  runtime allocates the subnet at creation.
+- What remains of `node networks` once that exists — only guests no module declares, such as a test
+  bed's pool? And should it then be named for that, rather than for all routing?
+- The runtime's own default bridge, which containers attach to when no module network is named, is
+  not a module's network. Is it derived from the machine, declared by the module that owns the
+  runtime, or left as the one constant?
+- Should the preview say which of a machine's networks are the mesh's and which are not, so a range
+  that exists to protect a leftover is visible as such?

04-ISSUES/142-the-host-is-the-one-thing-the-mesh-does-not-deliver/00-report.md

@@ -0,0 +1,76 @@
+---
+status: located
+opened: 2026-09-29
+located-in:
+  - mesh-host internal/upgrade
+  - mesh-host cmd/mesh-host
+  - mesh-controller (no build source for the host; no resource delivers it)
+fixed-by:
+amended-design: 03-DESIGN/01-to-be/05-the-node-host.md
+---
+
+# 142 — The host is the one thing the mesh does not deliver
+
+## What was observed
+
+A change to the host was merged and could not reach any machine without a person copying a file.
+
+Checked on the mesh of four machines, 2026-09-29:
+
+- **The host is not a build target.** Asked what had been built for it, the control plane answered
+  `nothing has been built for mesh-host`. A merge on the forge builds every changed module and the
+  control plane itself, because the control plane is a module. The host is not one, and nothing
+  builds it.
+- **No declaration delivers it.** No resource kind names an executable to place on a machine, and
+  nothing on a machine fetches one.
+- **The half that recovers from a bad host exists and is unused.** `internal/upgrade` can report that
+  the executable this process started from has been replaced on disk, and records which version last
+  completed a reconcile so a shell script can roll back a host that will not start. The launcher reads
+  that record and rolls back. But `Replaced()` is called by nothing except its own tests — the
+  recovery is wired and the delivery was never built.
+- **Every machine runs a byte-identical binary, stamped by hand.** All four carry the same size and
+  the same timestamp, from the last time somebody built it on a workstation and copied it out. No
+  package owns the file.
+
+## Why it matters beyond this instance
+
+**The component that implements updating is the one thing not updated.** The mesh's stated shape is
+that a push produces the right builds and they reach the machines running them with nobody asking. It
+is true of every module and of the control plane. It is false for the host, which is what applies all
+of them.
+
+**It is a bootstrap problem being answered by a person.** The host cannot be an ordinary module
+because the host is what applies modules; a module that replaces the thing applying it has to survive
+its own replacement. That is a real difficulty, and the work already done — noticing that the
+executable changed, recording a known-good version, a launcher that rolls back — is the hard half of
+solving it. What is missing is the easy half, and its absence makes the hard half dead code.
+
+**A hand-copied binary has no record anywhere.** Nothing says which version a machine runs, so
+nothing can say a machine is behind, and the mesh's own account of itself — every machine current with
+its source — cannot include the host. Four machines agreeing today is luck, not a property.
+
+**And it silently gates any change that starts in the host.** A change that needs the host to report
+something new cannot be rolled out by merging it: the control plane must wait for a person, and until
+then it either refuses what depends on the new report or renders something wrong. That cost is paid by
+every future change of this shape, and it was paid today.
+
+## Open questions
+
+- How is the host delivered without being applied by itself? A candidate shape: the host is built like
+  anything else, published as an artifact, and the *running* host fetches and stages the next one, then
+  stands aside — which is what `Replaced()` was written for and what the launcher's rollback already
+  covers.
+- **Should this ride the bus, rather than becoming a mechanism of its own?** Everything else that
+  reaches a machine already does: a declaration is sent over it, a report comes back over it, and a
+  build announces what it produced on it, which is how a module's new version reaches the machines
+  running it. A host build announcing itself the same way, consumed by the host already running,
+  would make this the existing mechanism pointed at one more artifact rather than a second way of
+  delivering things. It would also give the machine somewhere to say which host it is running, on the
+  report it already sends.
+- What records which version of the host a machine runs, so "behind" is answerable? Nothing does now.
+- Does the host's version belong in its report, beside the other facts a machine states about itself?
+- Who decides when a machine takes a new host — the mesh, on a build, or an operator per machine as
+  with converging? The rollback path means a bad host costs a reconcile rather than a machine, which
+  argues for the former.
+- Does the same gap apply to the launcher and the units beside the binary, which are also files no
+  declaration names?