If you run into the following error while running your Ecto migrations
ReleaseTasks.migrate ** (Ecto.MigrationError) migrations can't be executed, migration name foo_bar is duplicated (ecto) lib/ecto/migrator.ex:259: Ecto.Migrator.ensure_no_duplication/1 (ecto) lib/ecto/migrator.ex:235: Ecto.Migrator.migrate/4
You can fix it by running 1 migration at a time
mix ecto.migrate --step 1
This happens when you are trying to run two migrations with the same name (regardless of the timestamps). By restricting it to run 1 migration at a time you won’t run into this issue.
Ideally you should not have 2 migrations with the same name :)