anchor.diff:  { stdenv
  -, asciidoc
  -, docbook_xml_dtd_45
  -, docbook-xsl
   , fetchurl
  -, libxslt
  -, xmlto
   
   , krb5_lib
   , libsodium
  
positive.code: }:
  
  let
    version = "4.2.2";
  in
  stdenv.mkDerivation rec {
    name = "zeromq-${version}";
  
negative.code:     url = "https://github.com/zeromq/libzmq/releases/download/v${version}/"
        + "${name}.tar.gz";
      hashOutput = false;
      sha256 = "8f1e2b2aade4dbfde98d82366d61baef2f62e812530160d2e6d0a5bb24e40bc0";
    };
  
    buildInputs = [
      krb5_lib
  