{ stdenv, fetchurl, pkgconfig, gnutls, liburcu, lmdb, libcap_ng, libidn2, libunistring
, systemd, nettle, libedit, zlib, libiconv, libintl, libmaxminddb
, autoreconfHook
}:

let inherit (stdenv.lib) optional optionals; in

# Note: ATM only the libraries have been tested in nixpkgs.
stdenv.mkDerivation rec {
  pname = "knot-dns";
  version = "2.9.5";

  src = fetchurl {
    url = "https://secure.nic.cz/files/knot-dns/knot-${version}.tar.xz";
    sha256 = "1109a8ba212ff8ddfdbaf44a6f8fc13a2b880a98a9e54c19112ba72a1aacbf76";
  };

  outputs = [ "bin" "out" "dev" ];

  configureFlags = [
    "--with-configdir=/etc/knot"
    "--with-rundir=/run/knot"
    "--with-storage=/var/lib/knot"
  ];

  patches = [
    # Don't try to create directories like /var/lib/knot at build time.
    # They are later created from NixOS itself.
    ./dont-create-run-time-dirs.patch
  ];

  nativeBuildInputs = [ pkgconfig autoreconfHook ];
  buildInputs = [
    gnutls liburcu libidn2 libunistring
    nettle libedit
    libiconv lmdb libintl
    libmaxminddb # optional for geoip module (it's tiny)
    # without sphinx &al. for developer documentation
  ]
    ++ optionals stdenv.isLinux [ libcap_ng systemd ]
    ++ optional stdenv.isDarwin zlib; # perhaps due to gnutls

  enableParallelBuilding = true;

  CFLAGS = [ "-O2" "-DNDEBUG" ];

  doCheck = true;
  doInstallCheck = false; # needs pykeymgr?

  postInstall = ''
    rm -r "$out"/lib/*.la
  '';

  meta = with stdenv.lib; {
    description = "Authoritative-only DNS server from .cz domain registry";
    homepage = "https://knot-dns.cz";
    license = licenses.gpl3Plus;
    platforms = platforms.unix;
    maintainers = [ maintainers.vcunat ];
  };
}