`--whitelist <whitelistfile>`, or `-w <whitelistfile>`: Use the given whitelist file
to remove hosts from the generated hosts file.
+#### Using NixOS:
+
+To install hosts file on your machine add the following into your `configuration.nix`:
+
+```haskell
+ networking.extraHosts = let
+ hostsPath = https://raw.githubusercontent.com/StevenBlack/hosts/master/alternates/fakenews-gambling-porn-social/hosts;
+ hostsFile = builtins.fetchurl hostsPath;
+ in builtins.readFile "${hostsFile}";
+```
+
+* NOTE: The call to `fetchurl` is impure.
+Use `fetchFromGitHub` with the exact commit if you want to always get the same result.
+
## How do I control which sources are unified?