We use tags to mark release points.
Tags are easy to add:
git tag -a prod-0.9.7 -m "add analytics"

But this is only half the picture.
Tags do not get pushed with:
git push
-- tag option must be added to push the tags:
git push --tag

It is also esy to remove the tags:
git tag -d prod-0.9.7
git push origin :refs/tags/prod-0.9.7