anchor.diff:      cp -v ./data/colormgr $out/etc/bash_completion.d
     '';
   
  +  passthru = {
  +    srcVerification = fetchurl rec {
  +      inherit (src)
  +        outputHash
  +        outputHashAlgo
  +        urls;
  +      sha1Urls =  map (n: "${n}.sha1") urls;
  +      pgpsigUrls = map (n: "${n}.asc") urls;
  +      pgpKeyFingerprint = "163EB 50119 225DB 3DF8F  49EA1 7ACBA 8DFA9 70E17";
  +      failEarly = true;
  +    };
  +  };
  +
     meta = with stdenv.lib; {
       description = "Accurately color manage input and output devices";
       homepage = http://www.freedesktop.org/software/colord/intro.html;
  
positive.code:     "--enable-nls"
      "--disable-strict"
      "--enable-rpath"
      (enFlag "libgusb" (libgusb != null) null)
      (enFlag "udev" (systemd_lib != null) null)
      "--disable-bash-completion"
      (enFlag "polkit" (polkit != null) null)
      "--enable-libcolordcompat"
      (enFlag "systemd-login" (systemd_lib != null) null)
      "--disable-examples"
      (enFlag "argyllcms-sensor" (argyllcms != null) null)
      "--disable-reverse"
      "--disable-sane"
      (enFlag "vala" (vala != null) null)
      "--disable-session-example"
      "--enable-print-profiles"
      "--disable-installed-tests"
  
negative.code: 
  let
    inherit (stdenv.lib)
      boolEn;
  in
  stdenv.mkDerivation rec {
    name = "colord-1.3.4";
  
    src = fetchurl rec {
      url = "https://www.freedesktop.org/software/colord/releases/${name}.tar.xz";
      sha256 = "7e79ba022148900da7c72033f8232eefeab8373da25768f4b32f5aeba53b2238";
      hashOutput = false;
    };
  
    nativeBuildInputs = [
  