anchor.diff:  
     outputs = [ "out" "lib" "man" ]; # "dev" would only split ~20 kB
   
  +  nativeBuildInputs = [ makeWrapper ];
  +
     buildInputs = [ openssl nettle expat libevent ]
       ++ lib.optionals withSystemd [ pkg-config systemd ]
       ++ lib.optionals withDoH [ libnghttp2 ];
  
positive.code: 
    postInstall = ''
      make unbound-event-install
    '';
  
    preFixup = lib.optionalString (stdenv.isLinux && !stdenv.hostPlatform.isMusl) # XXX: revisit
  
negative.code: , libevent
  , dns-root-data
  , pkg-config
  , makeWrapper
    #
    # By default unbound will not be built with systemd support. Unbound is a very
    # commmon dependency. The transitive dependency closure of systemd also
  