diff --git a/01-RESEARCH/011-the-module-graph/00-overview.md b/01-RESEARCH/011-the-module-graph/00-overview.md index 4935865..787b5fb 100644 --- a/01-RESEARCH/011-the-module-graph/00-overview.md +++ b/01-RESEARCH/011-the-module-graph/00-overview.md @@ -185,5 +185,6 @@ Struck-through rows are answered, with where. The rest are live. | What does an exclusion mean for something already installed? | Refuse the install, or surface the conflict and let it be decided. | | Are tiers a view of the graph, or a constraint on it? | If a tier is a computed level the word is a convenience. If *a tier may depend only on tiers below it* is to be enforced, it is a constraint and must be stated as one. | | Where does resolution happen — the mesh, or the platform's package manager? | The mesh must model mesh-level edges. Whether it also resolves operating-system packages decides whether a solver gets written. | +| How far may the control plane be split? | A single board over several contexts works because they are contexts *inside* one control plane with one interface. If a context becomes its own deployable with its own interface, the board is coupled to N of them and the composition has nowhere to live that tier 3 permits. A constraint on splitting, worth knowing before splitting. | | What does the pipeline schedule, once features are gone? | It schedules features today. The four categories they split into have different lifecycles, so the unit of work differs for each and needs naming. | | Should placement leave the catalogue? | A provision pins itself to a named node in the manifest. Placement is an inventory decision, and having it in the catalogue means a second node cannot provide the mesh's store without editing its consumer. | diff --git a/01-RESEARCH/011-the-module-graph/worked-provider.md b/01-RESEARCH/011-the-module-graph/worked-provider.md index 7abac32..cc54105 100644 --- a/01-RESEARCH/011-the-module-graph/worked-provider.md +++ b/01-RESEARCH/011-the-module-graph/worked-provider.md @@ -240,8 +240,31 @@ a context's interface, that interface is inadequate — discovered in the one pl cheap to notice, rather than the first time something else needs the same data and quietly reaches for the store instead. -If composing many calls turns out too slow, the answer is a projection the board owns and keeps -current from events — not access to somebody else's tables. +**But "the board calls each context's interface" is not quite it either**, and the objection is +right: if every context runs its own service with its own interface, the board is coupled to N +of them instead of N schemas, something has to compose them, and composition is logic — which +tier 3 says a surface does not hold. That moves the problem up a layer rather than solving it. + +**The skeleton already answers this and the argument above talked past it.** `work` and +`knowledge` are not separate services; they are **contexts inside the control plane**, alongside +the record, inventory, delivery and the rest — and `api` is listed there as *the one interface +every surface speaks to*. + +So the board speaks to **one** interface. Behind it the contexts stay separate: separate stores, +integrating through the record. But they are one tier, one repository, one deployable, and +coupling *within* a tier is not what the tier rule forbids. + +Which resolves the objection rather than deflecting it: the problem does move up a layer, and +the layer it moves to already exists and has this as its job. + +**The caveat is load-bearing.** This holds only while the contexts are not separate deployables. +The moment one becomes its own service with its own interface, the board is back to N clients, +something must compose them, and the composition has nowhere to live that tier 3 permits. That +is a real constraint on how far the control plane may be split, and it is worth knowing now +rather than discovering it by splitting. + +If composing even one interface turns out too slow, the answer is a projection the board owns +and keeps current from events — not access to somebody else's tables. ### Checked against the real consumers