Vault Can't Find: What a Live Audit Found That Code Review Never Would

A live audit exposed a hidden migration bug in credential storage.

The legacy vault had been unreachable for a long time, and write failures were being swallowed.

The old data turned out to be effectively unused, but the new vault had a few real missing records that were corrected.

The case shows why live-system checks matter when code depends on infrastructure that may no longer exist.