I don't see how more efficient that could be. If you used ```skip``` and the backlogCount was higher than the number of documents, you would get ```null``` instead of a truncated list of documents.

You could be using a cursor, get the ```count``` and then ```skip``` that number to get the last one, but not sure this is worth the hassle. You probably don't ask for 1000 backlog documents so getting a few dozens should not be too demanding on the database. And this is executed only once at the start of the appserver, so no big deal.