anchor.diff:      buildInputs = [ jansson libedit libxml2 libxslt ncurses openssl sqlite
                       dmidecode libuuid newt
                       lua speex
  -                    srtp wget curl iksemel ];
  -    nativeBuildInputs = [ util-linux pkg-config ];
  +                    srtp wget curl iksemel ]
  +                  ++ lib.optionals withOpus [ libopus opusfile libogg ];
  +    nativeBuildInputs = [ util-linux pkg-config autoconf libtool automake ];
   
       patches = [
         # We want the Makefile to install the default /var skeleton
  
positive.code:     sha256 = "1s9idx2miwk178sa731ig9r4fzx4gy1q8xazfqyd7q4lfd70s1cy";
    };
  
    # auto-generated by update.py
    versions = lib.mapAttrs (_: {version, sha256}: common {
      inherit version sha256;
  
negative.code:       make menuselect.makeopts
        ${lib.optionalString (externals ? "addons/mp3") ''
          substituteInPlace menuselect.makeopts --replace 'format_mp3 ' ""
        ''}
        ${lib.optionalString withOpus ''
          substituteInPlace menuselect.makeopts --replace 'codec_opus_open_source ' ""
          substituteInPlace menuselect.makeopts --replace 'format_ogg_opus_open_source ' ""
        ''}
      '';
  
  