#Shims and Package Managers

Nodeup preserves rustup-like shim behavior: one binary can be invoked through managed executable names and dispatch based on argv[0].

#Managed Aliases

Nodeup recognizes these executable names:

• node
• npm
• npx
• yarn
• pnpm

If the binary is linked or copied as one of those names, Nodeup:

1. Resolves the active runtime by directory override or global default.
2. Installs a missing version runtime selected by that active selector.
3. Plans the delegated command.
4. Runs the resolved executable with inherited stdio.

Normal management commands still use the nodeup executable name.

#Direct Dispatch

For node, npm, npx, and non-package-manager commands, Nodeup resolves the command under the selected runtime's bin/ directory.

On Windows, primary executable names are normalized:

• node -> node.exe
• npm, npx, yarn, pnpm, corepack -> <command>.cmd
• other commands -> <command>.exe

#packageManager Discovery

For yarn and pnpm, Nodeup searches for the nearest package.json from the current working directory upward.

If package.json contains packageManager, it must be a string in this format:

{
  "packageManager": "pnpm@10.32.1"
}

Strict rules:

• Supported managers are yarn and pnpm.
• Versions must be exact semantic versions.
• The requested command must match the configured manager.
• Unsupported managers and malformed values fail with invalid-input.
• Manager-command mismatches fail with conflict.

Corepack is out of scope. Nodeup uses the selected runtime's npm exec.

#yarn Mapping

yarn@1.x.y maps to the classic Yarn package:

npm exec --yes --package yarn@1.22.22 -- yarn ...

yarn@2+ maps to Yarn's CLI distribution package:

npm exec --yes --package @yarnpkg/cli-dist@4.13.0 -- yarn ...

When packageManager is absent and the runtime has bin/yarn, Nodeup runs it directly. Otherwise it falls back to:

npm exec --yes --package @yarnpkg/cli-dist -- yarn ...

#pnpm Mapping

Pinned pnpm maps to:

npm exec --yes --package pnpm@10.32.1 -- pnpm ...

When packageManager is absent and the runtime has bin/pnpm, Nodeup runs it directly. Otherwise it falls back to:

npm exec --yes --package pnpm -- pnpm ...

#which Behavior

nodeup which yarn and nodeup which pnpm use the same planning rules as execution.

• Direct mode prints the runtime's yarn or pnpm executable.
• npm-exec mode prints the runtime's npm executable because npm exec will run the package-manager CLI.

#Failure Examples

This fails with conflict:

{
  "packageManager": "pnpm@10.32.1"
}

yarn install

This fails with invalid-input:

{
  "packageManager": "pnpm@10.x"
}