Tags are used to selectively apply checks and constraints to packages. Tags are defined in a package configuration file located in your package’s root directory.
commonality.json
{
  "tags": ["ui", "buildable", "private", "beta"]
}
Commonality Studio is the best way to create and edit tags for packages. Start Studio in any JavaScript project by running: npx commonality studio
Tags allow you to group packages by their purpose, concern, or domain without a tight coupling to directory structure. Below are some examples for inspiration but tags can be used to create any grouping that best suits your project.

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Tooling

Tags can be used to enforce a consistent toolchain for subsets of packages. Examples:
  • Check that packages with the buildable tag have build and dev scripts.
  • Check that packages with the testable tag have a test script and a vitest.config.ts file.
  • Check that packages with the typed tag have typescript as a devDependency.

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Concern

Tags can be used to create a hierarchy of packages based on their concern. Examples:
  • Enforce that no package can depend on a package with the tag deployable.
  • Enforce that packages with the tag config can only depend on packages also with the tag config.
  • Enforce that a database utility package with the tag data cannot depend on packages with the tag ui.

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Domain

Tags can be used to create separation between teams or domains working in the same monorepo.
  • Limit that packages with the tag marketing can only depend on packages with the tag marketing or shared.

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Workflow

Tags can be used to create workflows like deprecating or creating beta warnings.
  • Enforce that packages with the tag high-stability cannot depend on package with the tag beta.
  • Enforce that no package can depend on a package with the tag deprecated.