anchor.diff: -{ fetchurl, stdenv, pkgconfig, gnome3, python3, dconf
  +{ fetchurl, stdenv, pkgconfig, gnome3, python3, dconf, gobjectIntrospection
   , intltool, libsoup, libxml2, libsecret, icu, sqlite
  -, p11-kit, db, nspr, nss, libical, gperf, makeWrapper, valaSupport ? true
  +, p11-kit, db, nspr, nss, libical, gperf, makeWrapper
   , vala, cmake, ninja, kerberos, openldap, webkitgtk, libaccounts-glib, json-glib }:
   
   stdenv.mkDerivation rec {
     name = "evolution-data-server-${version}";
     version = "3.28.0";
   
  +  outputs = [ "out" "dev" ];
  +
     src = fetchurl {
       url = "mirror://gnome/sources/evolution-data-server/${gnome3.versionBranch version}/${name}.tar.xz";
       sha256 = "1ybyyy6nls11az8lbri1y9527snz5h7qbhyfqvk0vc6vzvald5gv";
     };
   
  -  passthru = {
  -    updateScript = gnome3.updateScript { packageName = "evolution-data-server"; };
  -  };
  -
     nativeBuildInputs = [
  -    cmake ninja pkgconfig intltool python3 gperf makeWrapper
  -  ] ++ stdenv.lib.optional valaSupport vala;
  +    cmake ninja pkgconfig intltool python3 gperf makeWrapper gobjectIntrospection vala
  +  ];
     buildInputs = with gnome3; [
       glib libsoup libxml2 gtk gnome-online-accounts
       gcr p11-kit libgweather libgdata libaccounts-glib json-glib
  
positive.code: 
    propagatedBuildInputs = [ libsecret nss nspr libical db ];
  
    # uoa irrelevant for now
    cmakeFlags = [
      "-DENABLE_UOA=OFF"
    ] ++ stdenv.lib.optionals valaSupport [
      "-DENABLE_VALA_BINDINGS=ON"
      "-DENABLE_INTROSPECTION=ON"
      "-DCMAKE_SKIP_BUILD_RPATH=OFF"
    ];
  
    enableParallelBuilding = true;
  
    preFixup = ''
      for f in $(find $out/libexec/ -type f -executable); do
  
negative.code:     done
    '';
  
    passthru = {
      updateScript = gnome3.updateScript {
        packageName = "evolution-data-server";
      };
    };
  
    meta = with stdenv.lib; {
      description = "Unified backend for programs that work with contacts, tasks, and calendar information";
      homepage = https://wiki.gnome.org/Apps/Evolution;
      license = licenses.lgpl2;
      maintainers = gnome3.maintainers;
      platforms = platforms.linux;
  