Relation Schemas and Attribute Types

I have a MySQL db with a field called “effective_at” that has a type of “datetime”. I would like the read type of the attribute to be a ruby DateTime. With infer = true I get a ruby Time returned. I have tried overriding the attribute in the schema…

attribute :effective_at, Types::DateTime, read: Types::Nominal::DateTime

And I have tried setting infer = false with out achieving the result I would like.

I have gone over the guides and this seems like it should be straight forward. Can someone give some guidance?
Many Thanks!