There are ways of removing compile time bugs by making everything code refs and then eval'ing them before switching but that won't fix run-time bugs.

I was hinting at running tests on the new stuff before it's accepted by the proxy process and supercedes the old stuff. Something like

if (check_for_new_stuff($new_stuff_location))
{
  my $new_stuff = do $new_stuff_location;
  if (run_time_tests($new_stuff))
  {
    $old_stuff = $new_stuff;
  }
}
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