I think many users, not just I, need custom fields, like phone, address, et.c. Can I refactor list of custom attributes with their validation like that:

config.fields = [:email, :phone]

validates :email, presence: true, email: true
validates :phone, numericality: { only_integer: true }, allow_nil: true

Is there any way?

If no, I want to refactor this gem and provide the ability to make a custom fields