Debugging

Turned a non-deterministic end-to-end suite (25–37 failures varying per run) into 302 tests passing with zero failures, without skipping tests or weakening assertions — and, in review, empirically proved that three of four proposed production changes were unnecessary.

Corrected tens of thousands of corrupted production records (~33k in one case) with no maintenance window, using reusable CLI commands with dry-run, rollback files, batch auditing and event re-publishing — a "correction command" pattern the team then reused.