anchor.diff: -{ stdenv, fetchurl, pkgconfig, intltool, itstool, libxml2, gtk3, openssl, gnome3, gobject-introspection, vala, libgee
  +{ stdenv, fetchurl, pkg-config, intltool, itstool, libxml2, gtk3, openssl, gnome3, gobject-introspection, vala, libgee
   , overrideCC, gcc6
   , mysqlSupport ? false, libmysqlclient ? null
   , postgresSupport ? false, postgresql ? null
  
positive.code: 
    hardeningDisable = [ "format" ];
  
    nativeBuildInputs = [ pkgconfig intltool itstool libxml2 gobject-introspection vala ];
    buildInputs = with stdenv.lib; [ gtk3 openssl libgee ]
      ++ optional (mysqlSupport) libmysqlclient
      ++ optional (postgresSupport) postgresql;
  
negative.code:     sha256 = "1j1l4dwjgw6w4d1v4bl5a4kwyj7bcih8mj700ywm7xakh1xxyv3g";
    };
    configureFlags = with stdenv.lib; [
      "--with-mysql=${if mysqlSupport then "yes" else "no"}"
      "--with-postgres=${if postgresSupport then "yes" else "no"}"
  
  