yarn

Every yarn install is a network request away from failure. The npm registry can go down, a corporate proxy can block a scoped package, or a build server can be air-gapped entirely. Yarn’s offline caching and mirroring features exist to eliminate that dependency: once packages are downloaded, they are stored locally and can be reused…

A dependency has a bug. The upstream fix is months away, or the maintainer is unresponsive, or the fix exists only in a pull request that has not been merged. Forking the repository is heavy: you lose the link to the original, you must maintain the fork, and your package.json points to a Git URL…

Publishing a package is the act of making it available for others to install. In Yarn Berry, the command is yarn npm publish. It packs the active workspace into a tarball and uploads it to a registry. The critical difference from Yarn Classic is the command name: Classic used yarn publish, Berry uses yarn npm…

A CI pipeline that installs dependencies without immutable installs is a pipeline that lies. It resolves new versions silently, rewrites the lockfile if needed, and produces a build that may not match what developers tested locally. Yarn Berry changes this default: when it detects a CI environment, it automatically enables immutable installs. A lockfile that…

Migrating from npm to Yarn is not a single command. It is a sequence of decisions: which Yarn version to target, whether to use Plug’n’Play or node_modules, how to convert the lockfile, and how to reconfigure the settings that npm stored in .npmrc. The most common mistake is running yarn install on an npm project…

1. Toolchain & Corepack 2. Project Initialization 3. Dependency Management 4. Installation & Lockfile 5. Running Scripts & Binaries 6. Workspaces (Monorepos) 7. Configuration (.yarnrc.yml) 8. Plug’n’Play (PnP) 9. Zero-Installs 10. Patching Dependencies 11. Publishing Packages 12. Cache & Registry Management 13. Environment Variables 14. CI/CD GitHub Actions (Standard) 15. npm to Yarn Migration