How should Nest handle jobs and scheduled tasks?

Definition:

A background job moves work out of the immediate request path, while a scheduled task starts work at a chosen time. Nest can integrate with queues and schedulers, but reliable execution still requires durable state and coordination. Multiple app instances can run the same schedule unless one owner or a distributed coordination mechanism is used.

Key points:

• Send slow work to a queue and let workers process it.

• Use retry limits, idempotency and failed-job monitoring.

• With multiple app instances, coordinate scheduled jobs to avoid duplicate runs.

• Acknowledge queue work only after its required state is durable; design retries for a worker crash after a side effect.

Interview point:

• Explain at-least-once delivery and idempotent handlers instead of claiming the queue guarantees one business effect automatically.