anchor.diff:            };
             publicKey = mkOption {
               default = null;
  -            type = types.nullOr types.string;
  +            type = types.nullOr types.str;
               description = ''
                 The public key data for the host. You can fetch a public key
                 from a running SSH server with the <command>ssh-keyscan</command>
  
positive.code:       };
  
        authorizedKeysFiles = mkOption {
          type = types.listOf types.unspecified;
          default = [];
          description = "Files from with authorized keys are read.";
        };
  
negative.code:       };
  
        keyFiles = mkOption {
          type = types.listOf types.path;
          default = [];
          description = ''
            A list of files each containing one OpenSSH public key that should be
  