Silent broker failure left 214 paid orders unshipped and undetected all weekend

A finance reconciliation at an unnamed company revealed 214 paid orders from the previous weekend had never been dispatched, with four customers already calling to complain. All system dashboards showed green because a years-old code change had silently swallowed the error — wrapping the messaging call in a try-catch that logged failures only as warnings. The root cause was a 12-minute broker outage during Saturday maintenance, which caused event publishing to fail after order rows and payments had already been committed to the database. The fix involved implementing the outbox pattern, writing events to a dedicated table within the same database transaction as the order, with a relay service handling retries and consumers deduplicating on event ID. An alert on the age of the oldest unsent outbox row has since caught three similar issues before they could silently accumulate into customer-facing problems.