anchor.diff:      libiconv lmdb libintl
       nghttp2 # DoH support in kdig
       libmaxminddb # optional for geoip module (it's tiny)
  +    libmnl # required for knot >= 3.1
       # without sphinx &al. for developer documentation
       # TODO: add dnstap support?
     ]
  
positive.code: { lib, stdenv, fetchurl, pkg-config, gnutls, liburcu, lmdb, libcap_ng, libidn2, libunistring
  , systemd, nettle, libedit, zlib, libiconv, libintl, libmaxminddb, libbpf, nghttp2
  , autoreconfHook, nixosTests
  }:
  
  
negative.code: 
  stdenv.mkDerivation rec {
    pname = "knot-dns";
    version = "3.1.0";
  
    src = fetchurl {
      url = "https://secure.nic.cz/files/knot-dns/knot-${version}.tar.xz";
      sha256 = "54323712e3cbc3d4c70a15777818fd2ff0de30cebb6c22e2946372b15b2653ed";
    };
  
    outputs = [ "bin" "out" "dev" ];
  