Seven years ago in 2012 I spoke at RubyConf China 2012. It was a technical talk on how to become a better developer, if you're interested…
ActiveRecord is without doubt the de facto ORM library for Rails and many Ruby web frameworks. Many developers however, do not like database migrations and prefer to use DSL for data mapping. Datamappify is created with the sole purpose of getting rid of the DB migration headaches.
Well, depending on your specific project, DB migrations might create more trouble than it’s worth. Besides, your code is already version controlled, so why create a separate version control for your DB schema?
As stated in the introduction, ActiveRecord is the most popular ORM in the rails community, it is actively developed and battle-tested. If your only grief with ActiveRecord is the DB migrations, why not just eliminate it be happy? ;)