ActiveJob and Sidekiq: not finding Job Class

Ruby on Rails
5 
class StripeRunnerJob < ActiveJob::Base
  queue_as :default

  def perform(guid)
    ActiveRecord::Base.connection_pool.with_connection do
      charge = Charge.find_by(guid: guid)
      return unless charge
      charge.process!
    end
  end
end

Sidekiq 3.2.6, Rails 4.2.beta4

No sidekiq initializer – the process starts with the following command: bundle exec sidekiq -q mailers, default

Thanks so much for your help! ActiveJob is still new enough that there isn’t much out there beyond the official docs.

One more sidenote, this job executes perfectly when ran inline, so the job itself “works” it’s just that sidekiq hates it, or actually doesn’t even know it.