Features
- Plug'n'Play (PnP) for zero-install deployments
- Offline caching of downloaded packages
- Workspace support for monorepos
- Constraints for enforcing dependency policies
Pros
- PnP eliminates node_modules for faster installs
- Strong offline support with reliable caching
- Built-in monorepo features with workspace constraints
Cons
- PnP mode has compatibility issues with some tools
- Yarn Classic (v1) vs Berry (v2+) split causes confusion
- Smaller community momentum compared to pnpm
Overview
Yarn is a JavaScript package manager originally created by Facebook as a faster, more reliable alternative to npm. Yarn Berry (v2+) introduced Plug’n’Play (PnP), a radical approach that eliminates the node_modules folder entirely, replacing it with a single .pnp.cjs file that maps packages directly.
The PnP approach offers significant benefits: instant installs (packages are already in the cache), deterministic dependency resolution, and the ability to commit your entire dependency tree to version control for true zero-install workflows.
Yarn also provides strong workspace support for monorepos, including constraints that let you enforce policies across all packages (like ensuring consistent dependency versions).
When to Use
Choose Yarn if you want PnP zero-install workflows or if your team is already using Yarn. For new projects without existing preferences, pnpm is generally the more popular choice in the current ecosystem.
Getting Started
corepack enable
yarn init -2
yarn add react react-dom
yarn dev