anchor.diff:      "--enable-failover"
       "--enable-execute"
       "--enable-tracing"
  -    "--enable-delayed-ack"  # Experimental in 4.3.2
  +    "--enable-delayed-ack"
       "--enable-dhcpv6"
       "--enable-paranoia"
       "--enable-early-chroot"
  
positive.code:     "--disable-use-sockets"
      "--disable-secs-byteorder"
      "--disable-log-pid"
      "--without-libbind"
      "--with-ldap"
      "--with-ldapcrypto"
    ];
  
    preInstall = ''
  
negative.code: , perl
  
  , coreutils
  , cyrus-sasl
  , gnused
  , iproute
  , iputils
  , krb5_lib
  , net-tools
  , openldap
  }:
  
  let
    version = "4.3.5";
  in
  stdenv.mkDerivation rec {
    name = "dhcp-${version}";
  
    src = fetchurl {
      url = "https://ftp.isc.org/isc/dhcp/${version}/${name}.tar.gz";
      hashOutput = false;
      sha256 = "eb95936bf15d2393c55dd505bc527d1d4408289cec5a9fa8abb99f7577e7f954";
    };
  
    nativeBuildInputs = [
  