It is worth applying through a referral. You only need to submit a CV. After that, if they are interested, you get a candidate preference questionnaire. This is not a filter, as far as I know, it is only information for teams that can be interested in you later. If you got the preference questionnaire, you almost certainly going to get two interviews, over GVC, coding in Google Docs. If your interviews are successful, you enter the matching phase: teams are going to consider working with you, and you are going to have to decide about them one at a time. (When deciding whether to accept the offer of a team, you don't have information about other projects or other teams interest in you. You can only talk to one team at a time.) If you accept, and they hire you, its over. If one of you declines, you can get matched with an other team.