Simon Willison’s Weblog

Sam Vilain converted Perl's history from Perforce to Git. [..] He spent more than a year building custom tools to transform 21 years of Perl history into the first ever unified repository of every single change to Perl. In addition to changes from Perforce, Sam patched together a comprehensive view of Perl's history incorporating publicly available snapshot releases, changes from historical mailing list archives and patch sets recovered from the hard drives of previous Perl release engineers.

— The Perl Foundation