G Suite (formerly Google Apps) organizations which signed up for Jostle through the Google Marketplace have some extra functionality in Library.
If you haven't already initialized your Library, you will need to create a user for it in your G Suite domain first. See this article for full details on how to initialize your Library.
Jostle uses a G Suite user and creates a Google Drive volume that is private to your organization. You can use an external Google Drive client to keep a local copy of your documents in sync with your Jostle Library. However if you do this you should modify files in Library rather than in Google Drive directly.