In JobHive, all users are registered via the same basic form but the account type depends on the user actions. For example, if a user tries to list a job and it’s approved by the admin, they get a company profile. You can require custom details from companies by adding attributes in Companies/Attributes section. If you mark attributes as Editable and Required, users trying to list a job will have to fill in these details (there will be an extra Complete Profile step in the listing process).
Unfortunately there’s no such option for job seekers yet because regular users don’t have front-end profile pages in the current version, but if you enable message attachments then job seekers can upload their CVs when sending a message via the Apply Now button.