右边图示说明了一个 XP 过程，它产生了正在开发的系统的一个增量。

• 用户故事是敏捷框架中最小的离散工作 (the smallest discrete piece of work)

Who decides on the velocity?

Tracker tracks the iteration, the testing for acceptance, the code quality, customer management, etc.

XP 工作流程

以及对应的实践 (XP Practices)

 

• Continuous Integration 持续集成
• 提倡集成系统多次，而且随着需求的改变，要不断的进行回归测试。使得团队保持一个较高的开发速度，同时避免了一次系统集成的恶梦。

• Energized Work

• Incremental Design
• Make small safe design improvements every day.

• Informative Workspace

• Pair Programming 结对编程
• 由两个开发人员在同一台电脑上共同编写解决同一问题的代码，通常一个人负责写编码，而另一个负责保证代码的正确性与可读性。

• Sit Together

• Slack
• 在进度落后时可以放弃的任务
• Some minor / low-priority tasks that can be dropped if you get behind and needed to meet overall commitments.
(2021 Final Exam) In eXtreme Programming (XP), what are slack tasks? Explain why we need them.
• Why: They provide some flexibility and room in the face of unexpected issues or delays, thus promoting a sustainable and healthy work environment for the development team.

• Stories
• 程序员如果无法理解 topic，则去 reasearch 然后 initial a Spike
• a Spike is a exploratory development activity that is used to research the uncertainty in the project.
• a spike is a skinny, minimal solution in throw-away code. The result of a spike is enough knowledge to attempt an estimate.
• Spikes are necessary in XP because they help teams deal with complexity.
• 如果故事太大，产品经理则 split stories into small tasks

• Ten-Minute Build
• Automatically build the whole system and run all of the tests in ten minutes

• Test-First Programming
• Write a failing automated test before changing any code.

• Weekly Cycle
• the name for an iteration in XP
• It is a planning and feedback loop that helps to ensure that the project is moving forward at a sustainable pace.
• 总结上一个周期的进展 ➡️ 为新周期选择新的 stories ➡️ 分配具体任务给团队成员

• Quarterly Cycle
• a longer-term planning process
• keep the detailed work of each weekly cycle in context of the overall product
• 关注于更大视角 (the big picture)，解决瓶颈 (bottlenecks)，决定季度周期的大局 (theme)

• Whole Team