jschoubben
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The loop closed on the workstation: the version landed, the launcher was replaced, the running host stood aside, and after one restart the launcher started a binary the mesh had compiled, published and delivered. The launcher goes as a file resource rather than inside the archive, and that is the safety rather than a preference. A file is written atomically, so the running launcher keeps the inode it started from; an archive writes in place with truncate and would cut a script a shell is reading. The manifest carries a second copy and a test refuses any drift from the one in packaging. Then it would have refused the first declaration it was asked to apply. The Makefile links in two facts the mesh's toolchain does not, on purpose, and one of them is the system the host was built for — read before anything is applied, so the failure is safe and total. Nothing reports it: the unit is active, the bus link is up, and the log says it is hearing what the node should be. Worse, the declaration that would fix it is the declaration it cannot apply, so the mesh cannot repair such a machine. Restored by moving the delivered versions aside and letting the launcher fall back, which is the fallback working as designed. 0142 already settles the version — it comes from where the component sits, not from its linker — and that is unimplemented. The system pin has no answer, and the candidates are a decision rather than a fix: put it in the path too, carry it in a file beside the binary, or stop pinning at link time at all, which is 0005's to change.
7.2 KiB
142 — the mesh can now build and publish its own host
2026-09-30. Both of ADR 0141's named gaps are closed; the host is not yet placed by the mesh.
What ADR 0141's insight named, and what each cost
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.
1. Nothing could compile it. The toolchain list was a closed set of typescript and python, and its own warning — every language is another implementation of the contracts modules share, so adding one commits to keeping N implementations in step — does not attach to Go. Go is how the host, the control plane and the builder are written, and none of them is a module in that sense: the host is what applies modules.
Closed by a Go toolchain naming a new base module, mesh-tools-go. Named and not pinned, so the mesh
answers with the copy it holds and moving compiler is a build rather than an edit to the control
plane's source (ADR 0044,
0142).
2. A version could not reach the path. An archive named a fixed path and nothing interpolated the
build into it, so nothing could ask for …/versions/<version>/.
Closed by ${version} in any value of a resource that uses an archive or a bundle. The version is
the artifact's digest, short, and not the commit: two builds of one commit are meant to be the same
bytes — the toolchains are -trimpath for that — so a content-addressed version means an unchanged
build resolves to the path it already had, where a commit-named path would move for an identical binary
and recreate everything reading it.
Three more things were in the way, and none was in the record
Found by doing it, in the order they appeared:
sourcesForturned every entrypoint into a.tsfile. One language's file extension, written into the code that serves every language. The extension is the toolchain's now.- The output directory was left to the compiler.
tsc --outDirmakes one;go build -owrites into a directory and does not create it, failing with a message about a path rather than about a build. Made for every toolchain, because which compilers are forgiving is not something a reader should have to know. - A bundle was refused if it named what it is built from. The reason — a bundle is the module's own directory compiled whole — holds for an interpreted language and cannot hold for a compiled one: a Go repository carries several commands, the host and its bootstrap among them, and "the module's own directory" is then not a package at all. A compiled bundle may now say which package; the refusal stands for every interpreted one.
And a fourth, in the base module itself: its first Dockerfile ran apt-get, and the golang image the
mesh holds is Alpine. That is
issue 136 in an image
rather than on a machine, and the build refused rather than a module failing later — which is the
behaviour that issue wants.
Measured: the mesh compiles its own host and publishes it to its own registry
$ mesh-controller build <the host's repository>
host-arch bundle artifact-store://mesh-host/host-arch/blobs/sha256:ad62528c…
mesh-host 1, built on novox from b5196e97
Fetched from the mesh's registry and opened:
mesh-host: ELF 64-bit LSB executable, x86-64, statically linked, stripped
$ ./mesh-host help
mesh-host — the node host
Statically linked matters: what a machine holds is a file rather than a container, so a binary needing a libc it did not bring is a delivery that works until a machine differs.
The host is a module now, with one bundle for arch built from cmd/mesh-host. A system is
required for a compiled artifact because a binary is pinned at link time so a host refuses to touch a
machine it was not built for (ADR 0005); arch is what all
four of this mesh's machines report themselves to be, and another system is another artifact and
another build.
What is left
The host module declares no resources, so nothing places the built bundle on a machine yet. That is
the next piece and it is the one with the interesting question in it: the resource is an archive
unpacked to …/versions/${version}/, applied by the host that is running, and the bootstrap is not
circular because the two are different versions (ADR 0141).
The host half of that mechanism — versions side by side, the newest runs, the running one stands aside
between reconciles, rollback picks a directory — is built and tested and has never had a version to
work on.
One thing worth noticing while writing it. The systems list exists because "the difference between two of them is a C library, not a kernel" — and a static Go binary has no C library. So one build would in fact run on all three. The pin is then a policy (a host refuses a machine it was not built for) rather than a necessity, which is a reasonable thing to keep and is worth knowing is a choice.
And a sharper one, asked as a question and worth its own record. The artifact's system is validated and then read by nothing: it does not reach the compiler, no machine is matched against it, and nothing chooses between two artifacts by it. The host built here is x86-64 because the build machine is, not because anything in the declaration said so — correct for this mesh by coincidence. That is issue 159.
Delivered, started, and one fact short (2026-09-30, later)
The loop closed. The launcher is delivered as a file resource rather than inside the archive, and
that difference is the safety: a file is written atomically — temp file, then rename — so the running
launcher keeps the inode it was started from, where an archive writes in place with truncate and would
cut the script a running shell is reading. The manifest carries a second copy of the launcher and a
test refuses any difference from packaging/nox-mesh-host-launch.
On the workstation, in order: the version landed, the launcher was replaced, the running host saw a
delivered version and stood aside, and after one restart of the unit the launcher started
/usr/lib/nox-mesh-host/versions/637f65559d16/nox-mesh-host. A host the mesh compiled, published,
delivered and started.
It would then have refused the first declaration it was asked to apply. The host's Makefile links in two facts the mesh's toolchain does not, and one of them — the system it was built for — is read before anything is applied. That is issue 161, and the machine is back on its hand-placed binary until it is answered.
The fallback is what made that safe, and it was not luck: the launcher runs the pinned version, or the newest delivered one, or the one placed by hand — so moving the delivered versions aside restored the machine in one step.