When working with monorepos, you often find yourself repeating the same dev dependencies across multiple workspaces. Maybe all your TypeScript packages need @types/node, or all your React packages need @testing-library/react. Instead of duplicating these dependencies in every package.json, workspace profiles let you define reusable sets of dev dependencies that can be shared across workspaces.

Defining profiles

Profiles are defined in your .yarnrc.yml file under the workspaceProfiles key. Each profile can contain dev dependencies and can extend other profiles:

workspaceProfiles:
  typescript:
    devDependencies:
      "@types/node": "^20.0.0"
      "typescript": "^5.0.0"

  react:
    devDependencies:
      "@testing-library/react": "^14.0.0"
      "react": "^18.0.0"

  fullstack:
    extends:
      - typescript
      - react
    devDependencies:
      "eslint": "^8.0.0"

Using profiles

To apply a profile to a workspace, add an extends field to its package.json:

{
  "name": "my-package",
  "extends": ["typescript"]
}

You can extend multiple profiles, and they will all be merged together. The default profile is always automatically included, even if you don’t specify it explicitly.

Profile inheritance

Profiles can extend other profiles, allowing you to build up complex configurations from simpler building blocks. When a profile extends another, all of its dev dependencies are inherited. If multiple profiles define the same dependency, the workspace’s own devDependencies take precedence, followed by profiles applied later in the resolution order.

Limitations

• Profiles only apply to dev dependencies. Regular dependencies must still be declared in each workspace’s package.json.

• If a workspace already declares a dev dependency in its package.json, profiles won’t override it. This ensures that workspace-specific requirements always take precedence over shared profiles.