anchor.diff:      };
   
       buildInputs = [
  -      cairo libXdmcp libpthreadstubs libxcb pcre python2 xcbproto xcbutil
  +      cairo libXdmcp libpthreadstubs libxcb pcre python3 xcbproto-py3 xcbutil
         xcbutilcursor xcbutilimage xcbutilrenderutil xcbutilwm xcbutilxrm
   
         (if alsaSupport   then alsaLib       else null)
  
positive.code: { cairo, cmake, fetchFromGitHub, libXdmcp, libpthreadstubs, libxcb, pcre, pkgconfig
  , python2, stdenv, xcbproto, xcbutil, xcbutilcursor, xcbutilimage
  , xcbutilrenderutil, xcbutilwm, xcbutilxrm, makeWrapper
  
  # optional packages-- override the variables ending in 'Support' to enable or
  
negative.code: assert i3Support     -> ! i3GapsSupport && jsoncpp != null && i3      != null;
  assert i3GapsSupport -> ! i3Support     && jsoncpp != null && i3-gaps != null;
  
  let xcbproto-py3 = xcbproto.override { python = python3; };
  in stdenv.mkDerivation rec {
      pname = "polybar";
      version = "3.4.1";
  
      src = fetchFromGitHub {
        owner = pname;
        repo = pname;
        rev = version;
        sha256 = "1z1m6dxh2i5vsnkzaccb9j02ab05wgmcgig5d0l9w856g5jp3zmy";
        fetchSubmodules = true;
      };
  
  