DuckRecord is a fork of ActiveRecord 5.0 and removed all Arel and DB-related things that aim to provide a powerful infrastructure for virtual model (a class which conforms ActiveModel’s protocol and not backed by a database), DuckRecord also support embeds_one and embeds_many association just like Mongoid does. There’s a dynamic form app demo shows how virtual model pattern (with many my practice) with ActiveRecord’s serialize can introduce NoSQL experience to traditional Rails-stack app.