prepend_callbacks

🔄 Overriding Callback Order with prepend: true

By default, subclasses append callbacks after parent callbacks. Use prepend: true to ensure your callback runs before inherited ones. This is crucial when you need to enforce preconditions before any parent logic executes.

class BaseRecord < ApplicationRecord
  before_save :log_save, prepend: true

  private

  def log_save
    Rails.logger.info("BaseRecord saving: #{self.id}")
  end
end

class SpecialRecord < BaseRecord
  before_save :validate_special, prepend: true

  private

  def validate_special
    throw(:abort) unless special_flag?
  end
end

Here, validate_special runs before log_save, even though log_save is declared in the parent. This helps you compose complex callback stacks predictably.