Setting up users in Broadleaf's Admin is as easy as assigning a role and determining what additional access (if any) you want the user to have. In addition to pre-defined roles, you can take any aspect of Broadleaf and give view or maintain (e.g., edit) access across any supported feature area. Check it out:

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Of course, if you would rather integrate to an authentication system (such as OAuth, Okta, or Active Directory), you can of course do that as well!