A runner (Letterbox.Runner) in Oban: each job an Oban job
(Letterbox.Runner.Oban.Worker), kept in the app's database, so it
outlives a deploy, and tried again with Oban's backoff, up to
Letterbox.Config's :max_attempts. A job waiting is not inserted twice.
The default runner when the app runs an Oban instance named Oban.
config :letterbox, Letterbox.Runner.Oban, queue: :mail, name: MyApp.Oban
config :my_app, Oban, queues: [default: 10, mail: 5]With no :queue, the jobs go on :letterbox, which the app's Oban must
run. Any other option of Oban.Job.new/2 (:priority, :tags) is
passed on.