Need for REST Crowd query of Groups and Users associations that is as a fast as that from SOAP

Please implement the ability to query all groups with memberships OR the ability to query all users with group memberships in the result in the REST interface.

Currently we use the SOAP interface to query groups matching active and user memberships are returned with this method in one transaction. This results in a query that takes only seconds. As with REST, we can only query the group names and then query each group for the members (or query the users and then query each for group membership), which takes on the scale of many minutes.

We are seeing 30-40 times slower given groups and users in the thousands. In order for us to adopt REST over SOAP, we cannot take such a performance hit.

Thank you for your time.