class ActiveJob::QueueAdapters::SidekiqAdapter

def enqueue_at(job, timestamp) #:nodoc:
  Sidekiq::Client.push \
    'class' => JobWrapper,
    'wrapped' => job.class.to_s,
    'queue' => job.queue_name,
    'args'  => [ job.serialize ],
    'at'    => timestamp
end