How to exclude package from being installed via symlink in pnpm?

When using pnpm for package management, one of its core features is using symlinks to link modules that are reused across different projects, saving disk space and improving efficiency. However, sometimes we may not want certain specific packages to be installed via symlinks, for example, to avoid version conflicts with specific packages or compatibility issues.

To exclude specific packages installed via symlinks in pnpm, you can use the following methods:

1. Using pnpmfile.js

pnpmfile.js is a file that allows you to customize installation behavior. By writing appropriate hooks in this file, you can modify the resolution or installation behavior of specific packages.

For example, if you do not want the package named example-package to be installed via symlinks, you can add the following code to pnpmfile.js:

js
module.exports = {
  hooks: {
    readPackage(packageJson) {
      if (packageJson.name === 'example-package') {
        packageJson.resolution = { tarball: 'https://example.com/path/to/example-package.tgz' };
      }
      return packageJson;
    }
  }
};

In this example, when installing example-package, we override its default installation method by directly specifying a tarball URL. This way, pnpm will download and extract the tarball directly instead of creating a symlink.

2. Using Configuration Options

Although pnpm's official support for directly configuring the exclusion of certain packages from symlink installation may not be as straightforward as with npm or yarn, you can indirectly achieve this through strategic dependency management. For example, placing certain packages in different workspaces or using the nohoist feature (though this is a Yarn Workspaces feature, it is sometimes used in pnpm with similar concepts).

Summary

By using the above methods, you can effectively control which packages should be installed via symlinks and which should be handled differently. This can help resolve specific dependency conflicts or meet particular project requirements. In practice, you may need to adjust the pnpmfile.js configuration based on your specific situation to achieve the best results.