I already have linked my StackOverflow Careers account with my GitHub account, but when I click on the GitHub link to add a new project I fall into a redirect loop.
This should be back and up and running now though I'm not sure I'd call it fixed just yet. We had an issue where we were not supplying a useragent to the github api which was resulting in a bunch of forbidden responses. The logic on our end wasn't (and still isn't) handling forbidden responses very well and caused the redirect loop, but we have fixed the useragent issue and alleviated the problem for now. We're in the process of coming up with a solution for using conditional requests which should significantly improve the reliability of our integration with the github api.