npm vs Yarn: Which Node Package Manager for CI?
Yarn pushed npm to improve, and today the gap is smaller than it was - but lockfile format, workspaces, and team habits still differ.
npm is the default bundled with Node. Yarn is an alternative package manager (Classic v1 and Berry v2+) known historically for speed, deterministic installs, and strong workspaces.
| npm | Yarn | |
|---|---|---|
| Bundled with Node | Yes | No (install separately) |
| Lockfile | package-lock.json | yarn.lock |
| CI install | npm ci | yarn install --immutable |
| Workspaces | Yes (basic) | Yes (mature) |
| Modern features | Steady improvements | PnP, zero-installs (Berry) |
In CI
npm ci gives a clean, reproducible install from package-lock.json with nothing extra to set up. Yarn offers mature workspaces and, in Berry, advanced features like Plug'n'Play and zero-installs that can speed CI. Performance is close for typical repos; the choice is often about existing lockfile and team familiarity more than raw speed.
Choosing for pipelines
Greenfield or want zero extra tooling: npm with npm ci. Need mature monorepo workspaces or Berry features: Yarn. Commit the lockfile, use the deterministic install command, and cache dependencies either way.
The verdict
Want the bundled, zero-setup default: npm. Want mature workspaces or Berry's PnP: Yarn. For most repos performance is similar - let your lockfile and workspace needs decide.