anchor.diff:    '') + extraPostFetch + ''
       cd "$TMPDIR"
     '' + (if purgeTimestamps then ''
  -    mtime="946713600"
  +    SOURCE_DATE_EPOCH="946713600"
     '' else ''
  -    mtime=$(find "${name'}" -type f -print0 | xargs -0 -r stat -c '%Y' | sort -n | tail -n 1)
  -    if [ "$NIX_BUILD_START" -lt "$mtime" ]; then
  +    SOURCE_DATE_EPOCH=$(find "${name'}" -type f -print0 | xargs -0 -r stat -c '%Y' | sort -n | tail -n 1)
  +    if [ "$NIX_BUILD_START" -lt "$SOURCE_DATE_EPOCH" ]; then
         str="The newest file is too close to the current date:\n"
  -      str+="  File: $(date -d "@$mtime")\n"
  +      str+="  File: $(date -d "@$SOURCE_DATE_EPOCH")\n"
         str+="  Build Start: $NIX_BUILD_START\n"
         echo -e "$str" >&2
         exit 1
       fi
     '') + ''
       echo -n "Clamping to date: " >&2
  -    date -d "@$mtime" --utc >&2
  +    date -d "@$SOURCE_DATE_EPOCH" --utc >&2
     '' + ''
       echo "Building Archive ${name}" >&2
  -    ${tar}/bin/tar --sort=name --owner=0 --group=0 --numeric-owner \
  -      --no-acls --no-selinux --no-xattrs \
  -      --mode=go=rX,u+rw,a-s \
  -      --clamp-mtime --mtime=@$mtime \
  -      -c "${name'}" | ${brotli}/bin/brotli ${lib.concatStringsSep " " brotliFlags} "$out"
  +    ${deterministic-zip.override { inherit version; }}/bin/deterministic-zip "${name'}" >"$out"
     '';
   } // removeAttrs args [ "name" "version" "purgeTimestamps" "downloadToTemp" "postFetch" "stripRoot" "extraPostFetch" ]))
   # Hackety-hack: we actually need unzip hooks, too
  
positive.code:     unzip
    ];
  }) // {
    inherit brotli tar purgeTimestamps;
  }
  
negative.code:         rest = if item == "tar" then lib.tail rest' else rest';
        in list ++ removeTarZip rest;
  
    urls' = (if url != null then [ url ] else [ ]) ++ urls;
  
    tarball = args.name or (baseNameOf (lib.head urls'));
  
    name' = args.name or (lib.concatStringsSep "." (removeTarZip (lib.splitString "." tarball)));
  in
  