mesh-catalog/modules/nodejs/README.md

nodejs

Node.js and npm as a module (novox/hq ADR 0477 §4, issue 1573).

• Declares the packages nodejs and npm. Today dev-tools, lab and mesh-build-node declare some of them too, which the resolver allows (ADR 0303); once they require node-toolchain instead (issue 1573's second step), this is the only module that declares them, and checks/toolchains refuses another.
• Provides node-toolchain with the machine's reach: a module that requires it composes only on a machine where this module is assigned. It is never pulled in for whatever asked, so nodejs is assigned to a node on purpose. Nothing requires it yet; dev-tools, lab and mesh-build-node will, in the second step.
• Holds no long-running resource, so it adds nothing to health-undeclared.

The node-engine never uninstalls a package, so when the users stop declaring nodejs and npm, nothing leaves a node that has this module.