If you are into Unix history, then I’ve got another gem for you. The Unix history Git repo at https://github.com/dspinellis/unix-history-repo.

The repository contains:

– snapshots of PDP-7, V1, V2, V3, V4, V5, V6, and V7 Research Edition,
– Unix/32V,
– all available BSD releases,
– the CSRG SCCS history,
– two releases of 386BSD,
– the 386BSD patchkit,
– the FreeBSD 1.0 to 1.1.5 CVS history,
– an import of the FreeBSD repository starting from its initial imports that led to FreeBSD 2.0, and
– the current FreeBSD repository.

I highly recommend exploring the branches and tags.