npm reads the project's own .npmrc, $HOME, and the global config. It
does not walk up parent directories (npm/npm#11437 is still open), so
the root .npmrc gates the root install and nothing else. Two nested
projects were resolving with no supply-chain quarantine at all:
scripts/whatsapp-bridge and plugins/platforms/photon/sidecar. Both now
carry their own gate, and `npm ci` in each returns its lockfile
byte-identical.
A project is a directory holding both package-lock.json and
package.json -- the pair npm resolves against. A lockfile with no
manifest beside it is a vendored artifact; nix/ keeps one for a
hash-pinned fetch that never consults npm config.
The required floor is read from the root .npmrc instead of hardcoded,
so the standard is raised in one place. A nested project may be
stricter, never weaker.