For the record, I mistook the on_complete trigger from the example for sending a coderef to one of the job servers. Upon re-reading it, I see only the string code (1+2) goes to the servers... my bad.

  use Gearman::Client;
   my $client = Gearman::Client->new;
   $client->job_servers('127.0.0.1', '10.0.0.1');

    $taskset->add_task( "add" => "1+2", {
       on_complete => sub { ... }
    });
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It's still pretty magical imo, but nolonger seems like some kind of dark arts.