I'm pushing undef into the queue with

foreach ( 1 .. $config->{number_of_threads} ) {

    $q->enqueue(undef);
}
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and I think this will cause thread to return:

    while ( my $org = $q->dequeue() ) {

        parse_org( $org, $mech );
        $pq->enqueue($org);
    }

    say "Finishing worker [$thread_id]";

    return;
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Also I have Finishing worker [SOME_ID] in the output...