1. Greenhouse Support
  2. All Recruiting topics
  3. Candidates and applications
  4. Custom fields

Immutable field key overview

An immutable field key is generated each time you create a new custom option in Greenhouse Recruiting. This key enables downstream apps, like HRIS and other integrations, to detect the presence of your custom fields in exported data.

In this article

Find an immutable field key

When you create a new custom option in Greenhouse Recruiting, an immutable field key is automatically generated.

Note: It isn't possible to manually name or edit your immutable field key.

To find an immutable field key, navigate to Configure > Custom Options > then select the type of company metadata, like candidate or offer fields.

Find your custom field in the list, and click on it to view details.

Example candidate custom fields are shown with Discipline highlighted in marigold

The immutable field key is listed at the bottom of the details page.

An example immutable field key named discipline is highlighted on the custom candidate field

Use an immutable field key

You can use immutable field keys for a variety of use cases.

  • Use HRIS Link with immutable field keys to match custom options in Greenhouse Recruiting to custom options in your HRIS.
  • Use integrations like BambooHR and Outmatch which require immutable field keys to help the integration run.