Yarn vs pnpm for CI: Which Package Manager Is Faster?
Both beat plain npm on speed, but Yarn (especially Berry with PnP) and pnpm take different routes to a fast, reproducible install.
Yarn is a mature package manager; Yarn Berry (v2+) adds Plug'n'Play to skip node_modules entirely. pnpm uses a content-addressed store with hard links and a strict, non-flat layout.
| Yarn | pnpm | |
|---|---|---|
| Install model | node_modules or PnP (Berry) | Linked content store |
| Install speed | Fast | Fast (often fastest) |
| Lockfile | yarn.lock | pnpm-lock.yaml |
| CI install | yarn install --immutable | pnpm install --frozen-lockfile |
| Strictness | Looser (Classic) / strict (PnP) | Strict by default |
In CI
pnpm is typically the fastest with the smallest disk footprint and strict resolution out of the box. Yarn Berry's PnP can also be extremely fast and cache-friendly, but PnP sometimes needs package compatibility shims. Yarn Classic is stable and widely used but slower than both modern options. Pick the immutable/frozen flag in CI for reproducibility.
Cache the right thing
Cache the pnpm store or Yarn's cache/.yarn directory keyed on the lockfile. Both run identically on CI runners; offloading the heavy install to faster managed runners shortens the slowest part of the job.
The verdict
Want the fastest installs and strictness with minimal fuss: pnpm. Already on Yarn and want PnP's zero-install cache model: Yarn Berry. Commit the lockfile and use the immutable/frozen flag on either.