No, it's GNU CVS, but it does work well enoughish...
they use a shitty BSD clone called Open CVS
Or not.
yes they do
You do realize who Ted Unangst is, right?
If he says "we use GNU CVS" you might consider believing him.
You might consider cross-referencing the authors of commits to the LibreSSL project with the authors of comments in this thread. You might be surprised.