{
  nixpkgs ? import <nixpkgs> {},

  kasyncSrc ? nixpkgs.fetchgit {
    url = "https://anongit.kde.org/kasync.git";
    rev = "8a68ad7da7f9d7d10d249a16a474fa7ca82517be";
    sha256 = "1v55my24d3zhllw77sjzngs6cwddjqf9xw9v0hkwk2gq2znwp6g8";
    fetchSubmodules = true;
  },

  kimap2Src ? nixpkgs.fetchgit {
    url = "https://anongit.kde.org/kimap2.git";
    rev = "62df1b858b3fd7c6c4b3229ff5051c0e4996b1be";
    sha256 = "1q43dzza1v5kjsvzisw5j2750550596s6hra45xbqny08hkpk355";
    fetchSubmodules = true;
  },

  kdav2Src ? nixpkgs.fetchgit {
    url = "https://anongit.kde.org/kdav2.git";
    rev = "830f07b99dc8badf5df40edb81cbac63a3ddb3c4";
    sha256 = "1da6ivjjq9bh855jiv0kzxi83z736iazn747gkaj261ai8qn7spz";
    fetchSubmodules = true;
  },

  sinkSrc ? nixpkgs.fetchgit {
    url = "https://github.com/KDE/sink";
    rev = "e1a6d6f5bbaeeffd92a2049849b75e248c2d492b";
    sha256 = "196vqd7gk93mfizxnfz918rs5g3723ndarx79x84q8qvk7bngc0v";
    fetchSubmodules = true;
  },

  kubeSrc,

  cmakeBuildType ? "Debug"
}:

rec {
    kasync = stdenv.mkDerivation {
        name = "kasync";
        nativeBuildInputs = with nixpkgs; [ cmake ninja ccache ];
        buildInputs = with nixpkgs; with qt5;
        [ extra-cmake-modules qtbase ];

        src = kasyncSrc;

        inherit cmakeBuildType;
    };

    kimap2 = stdenv.mkDerivation {
        name = "kimap2";
        nativeBuildInputs = with nixpkgs; [ cmake ninja ccache ];
        buildInputs = with nixpkgs; with qt5; with kdeFrameworks;
        [ extra-cmake-modules qtbase kcoreaddons kcodecs kdeApplications.kmime cyrus_sasl ];

        src = kimap2Src;
        inherit cmakeBuildType;
    };

    kdav2 = stdenv.mkDerivation {
        name = "kdav2";
        nativeBuildInputs = with nixpkgs; [ cmake ninja ccache ];
        buildInputs = with nixpkgs; with qt5; with kdeFrameworks;
        [ extra-cmake-modules qtbase qtxmlpatterns kcoreaddons ];

        src = kdav2Src;

        inherit cmakeBuildType;
    };

    sink = stdenv.mkDerivation {
        name = "sink";
        nativeBuildInputs = with nixpkgs; [ cmake ninja ccache ];
        buildInputs = with nixpkgs; with qt5; with kdeApplications;
        [
            extra-cmake-modules kmime kcontacts kcalcore
            flatbuffers lmdb xapian cyrus_sasl curl libgit2 readline
            qtbase

            kasync kimap2 kdav2
        ];

        cmakeFlags = [
            "-DCMAKE_CXX_FLAGS=-fdiagnostics-color=always"
            "-DCMAKE_EXPORT_COMPILE_COMMANDS=1"
        ];

        src = sinkSrc;

        inherit cmakeBuildType;
    };

    kube = stdenv.mkDerivation {
        name = "kube";
        nativeBuildInputs = with nixpkgs; [ cmake ninja ccache ];
        buildInputs = with nixpkgs; with qt5; with kdeFrameworks; with kdeApplications; with libsForQt5;
        [
            extra-cmake-modules kcalcore kcodecs kcontacts kmime
            qtbase qtquickcontrols2 qtwebengine qgpgme

            sink kasync
        ];

        CCACHE_COMPRESS = 1;
        CCACHE_DIR = "/var/cache/ccache";
        CCACHE_UMASK = "007";

        cmakeFlags = [
            #"-DCMAKE_CXX_COMPILER_LAUNCHER=${nixpkgs.ccache}/bin/ccache"
            "-DCMAKE_CXX_FLAGS=-fdiagnostics-color=always"
            "-DCMAKE_EXPORT_COMPILE_COMMANDS=1"
        ];

        dontStrip = if (cmakeBuildType == "Debug") then 1 else 0;

        src = kubeSrc;
    };
}