jschoubben
60aea14935
Same gap as the control plane: load-bearing and unpinned. The substrate is what the control plane CONSUMES AND CANNOT GRANT ITSELF. Every module needing a database asks provisioning for one; the control plane needs one too and cannot ask itself, because it is not running yet. That circularity is not an awkwardness to work around — it is the definition, and anything on the wrong side of it must be raised by the bundle the host carries. Which answers 006's open question in the honest form rather than with a number. The identity provider is substrate only if the control plane DELEGATES authentication — then it cannot serve anybody before the provider exists and cannot grant itself a client. If it authenticates natively, the provider is an ordinary hosted service. So the count follows from a decision not yet taken, and asserting four was asserting that decision. The test also rules out the tempting wrong answer: an identity provider, a mail server and an analytics service are all infrastructure by any ordinary reading, and none are substrate, because the control plane starts and runs without them. Important is not the test. Records why the bundle is pinned by hand — it is applied when no mesh exists, so nothing can resolve a version or ask a registry — and why it must be self-contained, which makes it an artifact built on a machine with a network for a machine that may have none.
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status, initiated, touches, became
| status | initiated | touches | became | ||||
|---|---|---|---|---|---|---|---|
| active | 2026-08-23 |
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006 — The mesh designed from nothing
What is being investigated
What the mesh would look like if it were laid out today, with the requirements known and none of the accumulated shape — expressed as a skeleton: repositories at the root, modules inside them, and whatever turns out to be the right leaf unit below that.
The deliverables are skeleton.md — tiers, repositories and the four design
moves — and code-skeleton.md — the tier test, what a module looks like on
disk, and where today's catalogue lands.
Why
Every structural decision so far has been a correction: eight contexts replacing thirty-three modules (ADR 0015), domains replacing single-function modules (ADR 0017). A correction inherits the frame of the thing it corrects, and two of the mesh's oldest problems look unsolvable from inside that frame:
- The bootstrap circularity. The mesh needs a database, a bus, a registry and an identity provider. Those are modules the mesh installs. The mesh cannot install them before it exists. This has been worked around repeatedly and never designed away.
- Participation requires privilege. Everything assumes root on a machine whose packages and services the mesh owns. A phone cannot participate on those terms, and neither can a machine someone else administers.
Designing from nothing is a way to find out which parts of the current shape are requirements and which are residue.
And there is more residue than expected, from a knowable source. This began as a
dotfiles repository — the first two days of history adopt dotfiles, add per-node dotfile
overrides, and introduce service symlinking with an ignore file. The flat one-directory-per-tool
catalogue, linking rather than copying, adoption of already-configured machines, per-node
overrides, and the desktop modules are all inherited from that, not chosen for a mesh. Recorded
in 03-DESIGN/00-as-is/10-module-catalogue.md.
That makes this effort's question sharper than "what would we do differently": much of what looks like design is a generalisation of place files on my machines, never revisited because it was never stated as an assumption.
The requirements this is designed against
Stated by the operator, recorded here so the skeleton can be checked against them rather than against taste:
- The mesh manages multiple computers — full control, through modules installed to nodes.
- Mesh state lives in a database: which modules on which nodes, logs, configuration.
- Configuration has several touchpoints — tool surface, web interface, others — all hosted by the mesh itself.
- Connectivity is core: every node reachable from every other over a shared overlay, some nodes publicly exposed, firewalls configured.
- The mesh hosts applications — and requires some of them itself. This is the circularity.
- Arch Linux only for now; ideally any device, including phones, on lighter terms.
- The end goal is to operate an IT company on it — development, design, deployment, full circle, self-hosted. Personal cloud infrastructure.
- Agents make it self-improving and self-healing.
- It is end-to-end testable on one machine (ADR 0016).
Status
A first skeleton exists, with four design moves that the current shape does not have. It is
active because two of them are unproven and one contradicts a record that is already
accepted.
Finding worth stating up front: ADR 0015 names nine bounded contexts and none of them owns connectivity — no overlay, no resolution, no firewall, no ingress. Requirement 4 has no home in the accepted decomposition, while research 005 found reachability to be the only part of the catalogue where modules genuinely change together under one intent. The skeleton adds it.
Open questions
| Question | Why it is open |
|---|---|
| Does the record — the event log contexts integrate through — belong to the substrate or the control plane? | It is infrastructure by shape and domain by content. Placing it wrong reintroduces a circularity. |
| One repository per tier, or per context? | Already open from ADR 0015 as "catalogue destination — one repository or many". The skeleton assumes per tier and does not settle it. |
| Answered 2026-08-25 by the operator: a node is a managed machine inside the mesh, not an unprivileged something — and a disconnected node is still a node, in a different situation. The question posed a class distinction; the answer is that there is none, and what varies is state. Recorded as ADR 0036. | |
Answered 2026-08-25 — host-size.md. Measured: the absorption is smaller than the machinery that already applies state, and eight of ten adapters already carry no dependency. The risk is not size but direction, and it is two modules wide. The claim survives with its scope corrected — the host carries one concern, apply declared state on this machine, of which the six are instances. Recorded as ADR 0037, designed in 05-the-node-host.md. |
|
Answered conditionally, which is the honest form — 07-the-substrate.md. The substrate is what the control plane consumes and cannot grant itself. The identity provider qualifies only if the control plane delegates authentication; if it authenticates natively it is an ordinary hosted service. The count follows from a decision not yet taken, and asserting four was asserting that decision. |
|
Does feature survive? |
The skeleton splits it in two and argues the conflation is what makes the delivery pipeline hard to reason about. Unproven. |