example.rb

class Model
  default_scope where(deleted_at: nil)

  def destroy_without_callbacks
    self.deleted_at = Time.now.utc
    update_without_callbacks
  end

  def destroy
    run_callbacks :destroy do
      destroy_without_callbacks
    end
  end

  def self.find_with_deleted *args
    self.with_exclusive_scope { find(*args) }
  end

  def deleted?
    !deleted_at.nil?
  end
end