don't require password auth for sudo

server/configuration.nix

@@ -197,6 +197,7 @@
   # Select internationalisation properties.
   i18n.defaultLocale = "en_US.UTF-8";
 
+  security.sudo.wheelNeedsPassword = false;
   # Define a user account. Don't forget to set a password with ‘passwd’.
   users.users.procolix = {
     isNormalUser = true;
@@ -251,6 +252,7 @@
 
   # Enable the OpenSSH daemon.
   services.openssh.enable = true;
+  services.openssh.settings.PasswordAuthentication = false;
 
   # Enable xe-guest-utilities
   services.xe-guest-utilities.enable = true;

server/default.nix

@@ -18,8 +18,8 @@ let
       result="$(nix-build ${toString ./.} -A machine --no-out-link --eval-store auto --store ssh-ng://${host})"
       # shellcheck disable=SC2087
       ssh ${host} << EOF
-      nix-env -p /nix/var/nix/profiles/system --set "$result"
+      sudo nix-env -p /nix/var/nix/profiles/system --set "$result"
-      "$result"/bin/switch-to-configuration switch
+      sudo "$result"/bin/switch-to-configuration switch
       EOF
     '';
   };