anchor.diff:  , libXScrnSaver, libXcursor, mesa
   
   # optional dependencies
  -, libgnome_keyring # gnomeKeyringSupport
  -, gconf # enableGnomeSupport
  -, libgcrypt # enableGnomeSupport || enableCUPS
  -, nss, openssl # useOpenSSL
  -, libselinux # useSELinux
  +, libgnome_keyring # config.gnomeKeyring
  +, gconf # config.gnome
  +, libgcrypt # config.gnome || config.cups
  +, nss, openssl # config.openssl
  +, libselinux # config.selinux
   }:
   
   let
     mkConfigurable = stdenv.lib.mapAttrs (flag: default: getConfig ["chromium" flag] default);
   
     config = mkConfigurable {
  -    useSELinux = false;
  -    naclSupport = false;
  -    useOpenSSL = true;
  -    enableGnomeSupport = false;
  -    gnomeKeyringSupport = false;
  -    useProprietaryCodecs = true;
  -    enableCUPS = false;
  +    selinux = false;
  +    nacl = false;
  +    openssl = true;
  +    gnome = false;
  +    gnomeKeyring = false;
  +    proprietaryCodecs = true;
  +    cups = false;
     };
   
     sourceInfo = import ./source.nix;
  
positive.code:     linux_use_gold_binary = false;
      linux_use_gold_flags = false;
      proprietary_codecs = false;
      use_gnome_keyring = config.gnomeKeyringSupport;
      use_gconf = config.enableGnomeSupport;
      use_gio = config.enableGnomeSupport;
      disable_nacl = !config.naclSupport;
      use_openssl = config.useOpenSSL;
      selinux = config.useSELinux;
      use_cups = config.enableCUPS;
    } // stdenv.lib.optionalAttrs config.useProprietaryCodecs {
      # enable support for the H.264 codec
      proprietary_codecs = true;
      ffmpeg_branding = "Chrome";
  
negative.code:     which makeWrapper
      python perl pkgconfig
      nspr udev
      (if config.openssl then openssl else nss)
      utillinux alsaLib
      gcc bison gperf
      krb5
      glib gtk dbus_glib
      libXScrnSaver libXcursor mesa
    ] ++ stdenv.lib.optional config.gnomeKeyring libgnome_keyring
      ++ stdenv.lib.optionals config.gnome [ gconf libgcrypt ]
      ++ stdenv.lib.optional config.selinux libselinux
      ++ stdenv.lib.optional config.cups libgcrypt;
  
    opensslPatches = stdenv.lib.optional config.openssl openssl.patches;
  
    prePatch = "patchShebangs .";
  
    patches = stdenv.lib.optional (!config.selinux) ./enable_seccomp.patch
           ++ stdenv.lib.optional config.cups ./cups_allow_deprecated.patch;
  
    postPatch = stdenv.lib.optionalString config.openssl ''
      cat $opensslPatches | patch -p1 -d third_party/openssl/openssl
    '';
  
  