[dancer-users] Social Media Sign-up/Sign-in

For a side project web site I'd like to offer users the ability to sign-up and sign-in using their existing social media accounts. Looking at other web sites these days, it seems to be pretty much expected that you can do that. But I have no idea where to start adding this feature to my (Dancer2) app. So what I'm hoping is that someone else somewhere in the Dancer community has done this before and has code that I can steal^Wstudy. Any information you can share would be massively appreciated. And if I work out what I'm doing, I promise I'll produce a Dancer2 plugin to simplify the process and/or an article or two explaining how it's done. Cheers, Dave...