I've hunted this down using 'guix time-machine' and it looks like the
first commit where the version string returns 0 is
076e825dc5d585943ce820a279fffe4af09757fb. On that
commit 'guix time-machine --commit=076e... -- --version' returns 0 and
on the commit before that 5996aab354831d942b10253bc70217a4f2e6a247 we
get the commit as the version string.

Looking at the commits I'm guessing that the 076e825d commit interacts
with the af57d1bf commit 2 before it, and whether the guile is guile-3.0
or guile-final or guile-3.0-latest.

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Efraim Flashner   <efraim@flashner.co.il>   אפרים פלשנר
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