anchor.diff:    meta = with stdenv.lib; {
       description = "Dynamic Host Configuration Protocol (DHCP) tools";
       homepage = http://www.isc.org/products/DHCP/;
  -    license = licenses.isc;
  +    license = licenses.mpl2;
       maintainers = with maintainers; [
         wkennington
       ];
  
positive.code:     "--enable-tracing"
      "--enable-delayed-ack"
      "--enable-dhcpv6"
      "--enable-paranoia"
      "--enable-early-chroot"
      "--enable-ipv4-pktinfo"
      "--disable-use-sockets"
      "--disable-secs-byteorder"
      "--disable-log-pid"
      "--enable-binary-leases"
      "--without-libbind"
      "--with-ldap"
      "--with-ldapcrypto"
  
negative.code: }:
  
  let
    version = "4.4.0";
  in
  stdenv.mkDerivation rec {
    name = "dhcp-${version}";
  
    src = fetchurl {
      url = "https://ftp.isc.org/isc/dhcp/${version}/${name}.tar.gz";
      multihash = "Qmb7wcUA5NjnWMKWK5TUNwzKpkmyQLpFqNH2dgRTuX2vuC";
      hashOutput = false;
      sha256 = "4a90be0f22ad81c987f5584661b60a594f1b21c581b82bfba3ae60f89ae44397";
    };
  
    nativeBuildInputs = [
  