Some bugs announce themselves loudly. A null pointer in a hot path, a missing route that returns 404 to every request — the kind of thing that fails immediately and points straight at the cause. Others are quieter. They let most of the stack work correctly and only reveal themselves at the intersection of two independently correct but mutually incompatible assumptions. The azurerm_storage_table_entity failure was the second kind. This post is an account of a two-day investigation into a persistent 401 Unauthorized response on Terraform table entity operations, the four separate bugs we found along the way, and how pairing with GitHub Copilot shaped the investigation. The fix touched authentication, HTTP routing, upsert semantics, and stream lifecycle — each uncovered only after the previous one was resolved. You can read more about Topaz here: https://topaz.thecloudtheory.com/ The starting point Topaz already had table storage support: accounts, tables, entity insert and query.…