Warning: practicingruby.com is a subscription website. There isn’t currently a paywall, but when you register, you get a friend webpage that says that there would be a paywall if they weren’t switching payment providers. You need to give them your email address to register. I hooked up my github account, because the only permissions they wanted were public information, and I didn’t care, so I don’t know if hooking up your github account is also necessary, although I doubt it, because not everyone has a github account.
My apologies. I’m a subscriber and forget that I’m automatically signed in when I visit the site.