anchor.diff:      substituteInPlace Makefile.in --replace ' etc ' ' '
     '';
   
  +  enableParallelBuilding = true;
     nativeBuildInputs = [ pkgconfig ];
     buildInputs = [
  -    zlib bzip2 libxml2 openssl ncurses curl libiconv libmilter pcre2 libmspack
  +    zlib bzip2 libxml2 openssl ncurses curl libiconv libmilter pcre2 libmspack json_c check
     ] ++ stdenv.lib.optional stdenv.isLinux systemd
       ++ stdenv.lib.optional stdenv.isDarwin Foundation;
   
  
positive.code:     "--with-xml=${libxml2.dev}"
      "--with-openssl=${openssl.dev}"
      "--with-libcurl=${curl.dev}"
      "--with-system-libmspack"
      "--enable-milter"
    ] ++ stdenv.lib.optional stdenv.isLinux
      "--with-systemdsystemunitdir=$(out)/lib/systemd";
  
  
negative.code: { stdenv, fetchurl, pkgconfig
  , zlib, bzip2, libiconv, libxml2, openssl, ncurses, curl, libmilter, pcre2
  , libmspack, systemd, Foundation, json_c, check
  }:
  
  stdenv.mkDerivation rec {
  