Hi, this is Simon, one of the team members that worked on labeling. I'm not sure I understand what you mean by building feature sets. Regarding workflow, we are still open to suggestions, but the general concept is treating annotating a bunch of files as a feature.

1. Create a branch from the current state

2. Create an annotation project on that branch

3. Annotate a bunch

4. Commit to the branch

5. Repeat 3 and 4 like you do with code

6. Open a PR