How to reload a gem on every request in Development mode? [closed]

Answer 1

For an engine:

module Copycat
  class Engine < ::Rails::Engine
    if Rails.env.development?
      config.to_prepare do
        Rails.logger.debug "RELOADING COPYCAT"
        require_dependency Copycat::Engine.root.join('lib', 'copycat').to_s
      end

      config.after_initialize do
        # optional, without it will call `to_prepend` only when a file changes,
        # not on every request
        Rails.application.config.reload_classes_only_on_change = false
      end
    end
  end
end