I have just figured out why a lot of times I had sha256sum mismatches on tag archives (here included):

$ diff beakerlib-1.30-old/ beakerlib-1.30-new/
diff beakerlib-1.30-old/.git_archival.txt beakerlib-1.30-new/.git_archival.txt
4c4
< ref-names: HEAD -> master, tag: 1.30
---
> ref-names: tag: 1.30

Are there better ways of writing the .git_archival.txt to avoid the HEAD -> master inclusion? The describe-name already has the tag, is that sufficient for setuptools-scm? There are many projects affected by this :(

Also upstream issue: pypa/setuptools-scm#1030