I consider this brittle because:

  1. It has to be in a file to work.
  2. In its file, it has to be one long line, and it has to be the first line.
  3. It relies on a particular implementation of crypt.
$gkh=open+0;$_=$WptYp=<0>;while(s*(..)(.{8})**){$keG.=crypt$2,$1}$WptYp^=$keG;$WptYp=~y%\040-\x7f%%cd;print$WptYp=~m~(J.{3})~,"\n"

I didn't do much to obscure what this code does, but here's a short description:

<Reveal this spoiler or all in this thread>

After I started this, I wondered if there was something similar already here, and I found liverpole's signature. I'd be interested in other instances.

In reply to Brute force JAPH by kyle

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