# build-agent

The mesh's build machine as a role every machine can hold (novox/hq ADR 0190). It holds the node seat
`node-build-agent`: every holder pulls one build at a time from the role's one work queue when it is
idle, so a tier of many images is built by as many machines as hold the seat and are online, and a
machine that is off builds nothing and blocks nothing. The controller asks the role, never a machine;
the outcome names the machine that built it.

What a holding machine needs is what the builder always needed, said here once: a container runtime
(the socket is mounted), the artifact store as a provision, a workspace, and the bus credential. The code is `cmd/mesh-builder` in the mesh-controller repository, compiled from
that repository's main (`build.artifacts[].context`); this module ships the packaging.

Assign it to every machine with a container runtime. It replaces `builder`, the one-holder form of the
same thing; retire that once this is assigned where it was.

## The package registry (novox/hq ADR 0336)

The package registry (`npm-package-registry`, provided by the gitea module) is an optional requirement.
Genesis assigns the build agent before anything provides it, so the agent is assignable on a mesh with no
registry, and `mesh-controller.plan` and `node` list the requirement as unbound until the gitea module is
assigned; it then binds with no further act.

Until it binds, the agent on genesis's node reads the `genesis-package-registry` own-secret, which the
installer seals to it at the packages step: the forge it raised, the port, the npm path, the account
`mesh-builder` and its password. Issued outside the mesh, so no other machine is given one. A real binding
wins over it, and each build's log says which the build resolved from. A build that needs the registry (a
`package` artifact, an image whose Dockerfile names `.npmrc`, a TypeScript artifact with an `@novox/`
dependency) on an agent with neither fails before building, naming the machine. Go artifacts and images
that do not name `.npmrc` build without it. `manifest_test.go` holds the manifest to this.