About fetching libgit2: is it possible what fetched library has old uncompatible version?

Yes, that is a good point. What would you suggest to handle this? Should I write out a tracking file named something like sha that contains the currently installed sha? That way we can compare and wipe out if it's outdated.

Actually I could just write a file named identical to the sha and fs.stat that for testing.

I think, will be enough to parse ./vendor/libgit2/include/git2/version.h

Your solution will be simple

If this looks good to you @3y3 can you merge?

Ok, I'm ready to merge it.
I have question about checking python current realisation working fine, but if exclude users of python 1.*(seriously dinosaurs knows about github?), the checking can be simplified.

@3y3 the checking is between python2 and python3 not python1. On systems like Arch Linux python defaults to 3 which doesn't work here. python2 is the aliased form.

Oh - now it's clearly. Merged.

Awesome, thanks!