Replaced manually written SQL transformations with a fully modular, tested, and documented dbt project on Snowflake — with CI/CD that cut deployment errors by 80% and data refresh time by 70%.
The warehouse's transformation logic lived in dozens of untested, undocumented stored procedures maintained largely through tribal knowledge. Every schema change carried the risk of silently breaking a downstream report, and a full warehouse refresh ran for most of the night — leaving little room to recover if something failed.
Rather than patch the existing procedures, the transformation layer was rebuilt from the ground up on dbt, with version control and testing treated as first-class requirements rather than an afterthought.
Within two quarters, the warehouse went from a fragile black box to a transparent, testable system the whole team could contribute to with confidence.
Treating the warehouse like software — with version control, tests, and CI/CD — paid off far beyond the initial migration effort. New analysts could ship a transformation change with confidence instead of fear, and "the warehouse is broken" stopped being a recurring Monday-morning conversation.