While Rails gives us migrations as a tool to transform database schemas, there isn't a good way to perform data migrations out-of-the-box. Whether it's backfilling a column or correcting corrupted data, performing this kind of maintenance work can feel scrappy and ad-hoc. Devs may resort to pushing a background job from a migration, or (gasp!) opening a production console and modifying their data directly. This talk will dive into the `maintenance_tasks` gem, an open source library that was developed at Shopify to make it easier to manage maintenance tasks. We’ll talk about the motivation for developing the gem, how we built it, and how Shopify uses it to run data migrations across millions of shops. After this talk, you should feel confident adopting the gem in your own Rails applications!