autoload_and_threads.rb

autoload :Date, 'date'

module Kernel
  alias_method :original_require, :require

  def require(path)
    puts "Require invoked for #{path}"

    original_require(path).tap do |loaded|
      if loaded
        sleep 1
        puts "Loaded #{path}"
      end
    end
  end
end

threads = Array.new(10) do
  Thread.new { Date }
end

threads.each(&:join)