Shrinking a 130 GB Postgres to a Local Copy with Greenmask: What Worked and What Brok

Staging had grown past 130 GB, a full pg_dump was out of the question, seeds never reproduced real bugs, and the data was full of PII. This post walks through building a small, FK-consistent, masked subset of a Rails app’s Postgres with Greenmask . It covers virtual references for Rails associations that never got a database FK, and masking every user to user<ID>@example.test with a known dev password. It also goes through the six things that broke and how each was fixed: NULL-owner row...