Bulk add user to individual groups and projects

Problem

In my team I have ~30 groups and ~60 developers.

Each developer must be part of some groups. To assign a developer to a group I have to go the group page (in the Admin Area) and setup members from there. If a developer is part of 30 groups I have to go to each of the 30 groups separately and setup membership there. It is not funny...

Workaround

Use the group and project members API.

Proposal

Why not go to the page /users/[user_name]/projects and setup groups from there? I can already see their groups and projects, but I cannot update their groups membership.

Design

TBD