Yarn 4.0 released with new features, performance improvements and an enhanced UI

Yarn, the open-source package manager for managing dependencies in JavaScript projects, has released its latest version, Yarn 4.0. This new version requires Node.js 18+ and has introduced several changes to the creation of new projects. Notably, Zero-Install will not be enabled by default in new projects created with yarn init. Instead, these projects will use Corepack rather than yarnPath.

Yarn 4.0 also incorporates all official plugins, such as typescript and interactive-tools, by default. The syntax for the yarn workspaces foreach command has been slightly modified in this version.

Additional enhancements in Yarn 4.0 include a hardened mode, performance improvements, and an improved user interface. The release also introduces a fancy new website for Yarn.

In a significant shift, Prolog constraints have been deprecated from Yarn 4. They have been replaced by a new JavaScript-based engine that offers optional TypeScript support. We can read the following in the announcement: “The new optional enableConstraintsChecks setting will make Yarn run your constraints as part of yarn install. It's a handy way to surface errors before having to wait for the remote CI to raise them, and since the new engine is so fast, it has almost no impact on your install time.”