anchor.diff:      libstartup_notification libX11 pcre libev yajl xcb-util-cursor perl pango
       perlPackages.AnyEventI3 perlPackages.X11XCB perlPackages.IPCRun
       perlPackages.ExtUtilsPkgConfig perlPackages.TestMore perlPackages.InlineC
  +    xorgserver xvfb_run
     ];
   
     postPatch = ''
  
positive.code: 
    checkPhase = stdenv.lib.optionalString (stdenv.system == "x86_64-linux")
    ''
      ln -sf "${xdummy}/bin/xdummy" testcases/Xdummy
      (cd testcases && perl complete-run.pl -p 1)
      ! grep -q '^not ok' testcases/latest/complete-run.log
    '';
  
  
negative.code: { fetchurl, stdenv, which, pkgconfig, makeWrapper, libxcb, xcbutilkeysyms
  , xcbutil, xcbutilwm, libstartup_notification, libX11, pcre, libev, yajl
  , xcb-util-cursor, coreutils, perl, pango, perlPackages, libxkbcommon
  , xorgserver, xvfb_run }:
  
  stdenv.mkDerivation rec {
    name = "i3-${version}";
    version = "4.10.1";
  
    src = fetchurl {
      url = "http://i3wm.org/downloads/${name}.tar.bz2";
      sha256 = "1qjpbrfy5pnk5d0dh9zs96ppw3jwad1jcy529zy4ja68mdgz6b8b";
    };
  
    buildInputs = [
  