Guarantee at-least-once delivery for a critical analytics event?

This tests your ability to design for atomicity in distributed systems, specifically avoiding the dual-write problem. A strong answer proposes the Transactional Outbox pattern: atomically commit business data AND the event to an 'outbox' table in the same database transaction. A separate message relay process then sends events from the outbox. Finally, note the analytics consumer must be idempotent. A red flag is suggesting a fire-and-forget call with retries, which doesn't guarantee delivery if the service crashes post-commit but pre-send.