Access your site with http(s)://127.0.0.1/, configure your app to listen to 127.0.0.1 only and you are safe. Encryption is not necessary as there is no possibility for someone outside to listen: nothing goes outside of your computer, your app on your computer "talk" with your browser on your computer via an address witch cannot be used outside of your computer. And, as far as I know, localhost is always mapped to 127.0.0.1 at a system level. You could use it instead of 127.0.0.1 if you wish.