anchor.diff:      "--enable-dnstap"
       "--enable-dnscrypt"
       "--enable-cachedb"
  +    "--enable-ipsecmod"
  +    "--with-ssl=${openssl}"
  +    "--with-libexpat=${expat}"
  +    "--with-libevent=${libevent}"
  +    "--with-libhiredis=${hiredis}"
       "--with-dnstap-socket-path=/run/dnstap.sock"
       "--with-pthreads"
     ];
  
positive.code: 
  , expat
  , fstrm
  , libevent
  , libsodium
  , openssl
  
negative.code:     "https://unbound.net/downloads/unbound-${version}.tar.gz"
    ];
  
    version = "1.7.1";
  in
  stdenv.mkDerivation rec {
    name = "unbound-${version}";
  
    src = fetchurl {
      urls = tarballUrls version;
      multihash = "QmcfW5KZRoV58V37i2QhSqbBGg3FDqzRHL9xkjXEE9equB";
      hashOutput = false;
      sha256 = "56e085ef582c5372a20207de179d0edb4e541e59f87be7d4ee1d00d12008628d";
    };
  
    buildInputs = [
      expat
      fstrm
      hiredis
      libevent
      libsodium
      openssl
  