dbt-unit-testing is a dbt package that allows writing unit tests for a model and its logic by mocking its dependencies. This brings the engineering rigor of fast development feedback to the data ecosystem. Our teams use this package with Snowflake to practice test-driven development (TDD), although it was only feasible for simple transformations. The library certainly has rough edges when it comes to debugging failed test runs, but the ability to write unit tests on transformers as we develop the model provided a neat developer experience.