Blocking social media in NixOS

Add this to your NixOS Linux configuration.nix:

{
  networking.extraHosts =
    ''
      127.0.0.1 reddit.com
      127.0.0.1 www.reddit.com
      127.0.0.1 np.reddit.com
      127.0.0.1 old.reddit.com
      127.0.0.1 www.old.reddit.com

      127.0.0.1 news.ycombinator.com
      127.0.0.1 hckrnews.com

      127.0.0.1 twitter.com
      127.0.0.1 www.twitter.com
      127.0.0.1 mobile.twitter.com
    '';
}

On Windows, the file to modify is c:\windows\system32\drivers\etc\hosts.
On macOS, the file to modify is /private/etc/hosts