The best migration is no-migration. That is not having to move data at all. This becomes increasingly more important with larger datasets. One way of doing that is to simply serialize data in something like Protobuf and have a generic schema that rarely/never needs to be altered[1]. Adding a new field to the Protobuf is a no-op.

[1] https://kevin.burke.dev/kevin/reddits-database-has-two-table...