Package managers

pkgr runs the command you would have typed. Choosing the right tool is the whole job, so the rules are short and fixed.

For package.json

In order:

1. The packageManager field, if it names a known tool. This is the Corepack format, e.g. "packageManager": "pnpm@9.1.0" gives pnpm. Known names are npm, pnpm, yarn and bun.

2. A lockfile next to the manifest, checked in this order:

   Lockfile	Tool
   pnpm-lock.yaml	pnpm
   yarn.lock	yarn
   bun.lock	bun
   bun.lockb	bun
   package-lock.json	npm

3. npm, as the fallback.

An unrecognised packageManager value (say "foo@1") is ignored and detection falls through to the lockfile rather than producing a command that cannot run.

The command is always <tool> run <task>.

For Deno

deno.json and deno.jsonc always run as:

deno task <task>

Lockfiles are ignored.

Seeing the decision

pkgr prints the resolved command to stderr just before it runs, so you always see what was chosen:

> pnpm run build

If the wrong tool is chosen, set packageManager in package.json. That is the one source pkgr trusts above all others.