The PublicSuffix gem works great if you give it nice, clean domains WITHOUT a transfer protocol. But what if your application has one (or multiple) urls with or without protocols? LazyDomain assumes it could be either way and uses URI to make up the difference. Because URI can only parse a url WITH a protocol, Lazy Domain automatically adds 'http://' if it is not already present in a url. Now you can easily use PublicSuffix for varying urls.