XP avoids these problems through two key techniques: the programmer tests catch mistakes, and pair programming means that the best way to work on unfamiliar code is to pair with the expert.

• xp通过两种关键技术来避免这类的问题：通过程序员测试来捕获错误，成对编程则表明在不熟悉的代码上工作的时候最佳途径是找一个这方面的专家作为伙伴。