package.json

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A reference for Expo-specific properties that can be used in the package.json file.

package.json is a JSON file that contains the metadata for a JavaScript project. This is a reference to Expo-specific properties that can be used in the package.json file.

`install.exclude`

The following commands perform a version check for the libraries installed in a project and give a warning when a library's version is different from the version recommended by Expo:

npx expo start and npx expo-doctor
npx expo install (when installing a new version of that library or using --check or --fix options)

By specifying the library under the install.exclude array in the package.json file, you can exclude it from the version checks:

package.json

{
  "expo": {
    "install": {
      "exclude": ["expo-updates", "expo-splash-screen"]
    }
  }
}

`autolinking`

Allows configuring module resolution behavior by using autolinking property in package.json.

For complete reference, see Autolinking configuration.

`doctor`

Allows configuring the behavior of the npx expo-doctor command.

`reactNativeDirectoryCheck`

By default, Expo Doctor validates your project's packages against the React Native directory. This check throws a warning with a list of packages that are not included in the React Native Directory.

You can customize this check by adding the following configuration in your project's package.json file:

package.json

{
  "expo": {
    "doctor": {
      "reactNativeDirectoryCheck": {
        "enabled": true,
        "exclude": ["/foo/", "bar"],
        "listUnknownPackages": true
      }
    }
  }
}

By default, the check is enabled and unknown packages are listed.

`appConfigFieldsNotSyncedCheck`

Expo Doctor checks if your project includes native project directories such as android or ios. If these directories exist but are not listed in your .gitignore or .easignore files, Expo Doctor verifies the presence of an app config file. If this file exists, it means your project is configured to use Prebuild.

When the android or ios directories are present, EAS Build does not sync app config properties to the native projects. Expo Doctor throws a warning if these conditions are true.

You can disable or enable this check by adding the following configuration to your project's package.json file:

package.json

{
  "expo": {
    "doctor": {
      "appConfigFieldsNotSyncedCheck": {
        "enabled": false
      }
    }
  }
}