I finally bought an SSL certificate to keep your passwords away from others, and ensure you are receiving NuGet packages from the original site. Please meet https://nuget.hangfire.io (A grade on SSL Labs) and https://discuss.hangfire.io (A+ grade on SSL Labs).
You can still access private NuGet feed via regular HTTP – I haven’t added any redirects yet, because they may theoretically lead to different issues. However it is better to use HTTPS if possible, and for browsers I’ve turned on the Strict Transport Security feature.
Discussion forum is fully operating in HTTPS, with all the required redirects.