https://github.com/jj-vcs/jj is the next generation of version control systems. I love it. It uses got or mercurial underneath, so it's compatible with the got ecosystem, and treats the working directory a a commit(!), allows me to edit a previous commit, auto-rebasing subsequent computers and treats merge conflicts as version controlled entities, allowing me to resolve merge conflicts when it suits me, and not immediately. Ready for us to kick the tires!

Of course what people do outside of work matters. If they are insulting and ranting everywhere, constantly demanding free help on open source mailing lists, chances are they'll be similar at work too. If they are courteous and helpful in mailing lists, and have created 47 interesting projects at the same time, chances are they'll be productive at work too. When hiring, I'll use the tools at my disposal to evaluate a potential candidate. And there just are so many qualifications that aren't technical.