corepack prepare: Usage, Options & Common CI Errors

corepack prepare fetches and activates a specific Yarn or pnpm version.

corepack prepare downloads an exact package-manager version and, with --activate, makes it the default the shims resolve to. It is how you pin pnpm or Yarn deterministically in CI.

What it does

corepack prepare <pm>@<version> --activate downloads that package manager into Corepack's cache and sets it as the active version. It pairs with the packageManager field for full reproducibility, and can pre-warm the cache (corepack prepare --all) for offline use in air-gapped CI.

Common usage

Terminal

corepack enable
corepack prepare pnpm@9.5.0 --activate
corepack prepare yarn@4.3.1 --activate
corepack prepare --all                            # pre-cache for offline use
pnpm --version                                    # -> 9.5.0

Common errors in CI

"Error when performing the request" / "request to https://registry.npmjs.org ... failed" means Corepack could not reach the registry to download the version - check proxy/network or pre-cache with --all. "Cannot find matching keyid" / "Signature verification failed" is an older Corepack rejecting a newer package-manager signature; upgrade Node/Corepack. Without --activate, prepare only caches the version and does not switch to it, so the shim may still run a different one.

Options

Item	What it does
<pm>@<ver> --activate	Download and make it the active version
--all	Pre-cache all package managers (offline prep)
(no --activate)	Cache only; does not switch the active version