The Structure of node_modules and Phantom Dependency

The Structure of node_modules

The node_modules directory stores the libraries specified in package.json. Each library also has its own package.json, and the dependencies specified in that package.json are stored under a node_modules directory created inside the directory where the corresponding library is stored. At this point, if multiple libraries use the same version of a library as a dependency at the same time, that library is hoisted to the top-level path of the node_modules directory.

Source: https://toss.tech/article/node-modules-and-yarn-berry

Phantom Dependency

A phantom dependency is a phenomenon that occurs because of where duplicate libraries are located. A phantom dependency means you can use a library that is not specified in package.json. Because the version of this library is not clearly defined, it can cause version compatibility errors for other users.

References

• https://rushjs.io/pages/advanced/phantom_deps/
• https://toss.tech/article/node-modules-and-yarn-berry

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