Please consider changing
@{Storable::thaw( ... )}
to
my $ar = Storable::thaw( ... );
@$ar == 1 ? $ar->[0] : @$ar
so that
while (my $response = $q->dequeue)
works in addition to
while (my ($response) = $q->dequeue)
in the common case that only argument is passed to `enqueue`.