Jekyll won't install on OSX High Sierra out the box

It’s very much unlike Windows (if PC is what you mean I assume). I’m using MacOS’s (sort of unofficial, but also very much standard) homebrew, which takes care of packages in a unix-like way.

The error with build native gem extension from Stack Overflow seems to exclusively be about xtools, but my command line tools are up to date.

I’m trying to get rbenv installed now to combat the environment problems, but I can’t even do that as installing a newish version of Ruby fails on rbenv install. This is madness!