I'm (very) late to the party, but I just set up at the University of New Haven
https://math.newhaven.edu/webwork2/
WeBWorK 2.17 with Canvas, account auto-creation, and grade passback. Everything works like a charm, especially if one follows directions. The option of using fallback_source_of_username is brilliant, my settings are
$preferred_source_of_username = "lis_person_contact_email_primary";
$fallback_source_of_username = 'user_id';
$strip_address_from_email = 1;