public function delete($job_id = null)
    {
        $result = null;
        $this->hook->attach('job.delete.before', $job_id, $result, $this);

        if (isset($result)) {
            return (bool) $result;
        }

        $result = $this->session->delete("jobs.$job_id");
        $this->hook->attach('job.delete.after', $job_id, $result, $this);
        return (bool) $result;
    }