active_admin.rb

ActiveAdmin.register Post do
  index do
    column :title
    column :published_at
    default_actions
  end

  form do |f|
      f.inputs "Dettagli" do
        f.input :title
        f.input :body
        f.input :published_at
      end
      f.actions
    end
end

railsyard.rb

Railsyard::Backend.define_editor_for Post do
  label :title

  list do
    field :published_at
  end

  edit do
    field :title
    field :body
    field :published_at
  end
end