The Myth of Down Migrations; Introducing Atlas Migrate Down
Ever since my first job as a junior engineer, the seniors on my team told me that whenever I make a schema change I must write the corresponding "down migration", so it can be reverted at a later time if needed. But what if that advice, while well-intentioned, deserves a second look?
Today, I want to argue that contrary to popular belief, down migration files are actually a bad idea and should be actively avoided.
In the final section, I'll introduce an alternative that may sound completely contradictory: the new migrate down command. I will explain the thought process behind its creation and show examples of how to use it.
Since the beginning of my career, I have worked in teams where, whenever it came to database migrations, we were writing "down files" (ending with the .down.sql file extension). This was considered good practice and an example of how a "well-organized project should be."
Over the years, as my career shifted to focus mainly on infrastructure and database tooling in large software projects (at companies like Meta), I had the opportunity to question this practice and the reasoning behind it.
