Yarn supports three different ways to install your projects on disk. This document gives a quick overview of each of them, along with the pros and cons of each.

Note

All install modes are stable and production-ready. Yarn uses PnP installs by default, but the pnpm and node-modules linkers are first-class citizens as well, supported by a wide range of tests.

nodeLinker: pnp

For more details about Plug’n’Play installs, check the dedicated section.

Under this mode Yarn will generate a single Node.js loader file directory referencing your packages from their cache location. No need for file copies, or even symlinks / hardlinks.

Pros	Cons
Extremely fast	Less idiomatic
Content-addressable store	IDE integrations often require SDKs
Protects against ghost dependencies	Sometimes requires packageExtensions
Semantic dependency errors
Perfect hoisting optimizations
Provides a dependency tree API
Can be upgraded into zero-installs

Note

Yarn Plug’n’Play has been the default installation strategy in Yarn since 2019, and the compatibility story significantly improved along the years as we worked with tooling authors to smoothen the edges.

nodeLinker: pnpm

Under this mode, a flat folder is generated in node_modules/.pnpm containing one folder for each dependency in the project. Each dependency folder is populated with hardlinks obtained from a central store common to all projects on the system (by default $HOME/.yarn/berry/index). Finally, symlinks to the relevant folders from the flat store are placed into the node_modules folders.

Pros	Cons
Slower than PnP, but still very fast	Symlinks aren’t always supported by tools
Content-addressable store	Hard links can lead to strange behaviors
Protects against some ghost dependencies	Generic dependency errors
No need for IDE SDKs	Sometimes requires packageExtensions

Note

The pnpm mode is an interesting middle ground between traditional node_modules installs and the more modern Yarn PnP installs; it doesn’t decrease the performances much and provides a slightly better compatibility story, at the cost of losing a couple of interesting features.

nodeLinker: node-modules

This mode is the old tried and true way to install Node.js projects, supported natively by Node.js and virtually the entirety of the JavaScript ecosystem.

While we tend to recommend trying one of the two other modes first, it remains a solid option in case you face problems with your dependencies that you don’t have the time to address right now. Sure, your project may be a little more unstable as you won’t notice if ghost dependencies creep in, but it may be a reasonable trade-off depending on the circumstances.

Pros	Cons
Perfect compatibility with the whole ecosystem	Average speed
Optional support for hardlinks (nmMode)	No protection against ghost dependencies
No need for IDE SDKs	Imperfect hoisting due to the filesystem reliance