在本书中，作者Henrik Kniberg讲 述了他在一年的时间里，带领40人的团队实施Scrum的过程。他们试过了多种团队尺寸（3～12人）、sprint长度（2～6星期），定义“完成”的 不同方式，不同的backlog格式，各种测试策略，在多个Scrum团队之间进行同步的多种方式。他们还尝试过XP实践——持续集成、结对编程、测试驱 动开发等等，还试过了把XP跟Scrum组合。

本书描述的是一个成功敏捷团队的工作过程，没有理论、没有引用、没有脚注、没有废话。读者可以把它当作一些基础实践的入门指南，帮助团队进行正确实施——但不能模仿，你需要了解自己所处的环境，进而对具体实践做出取舍，创造出属于自己的过程。

免费下载此书：硝烟中的Scrum和XP（ 免费下载这本书（PDF） ）

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Scrum is an iterative incremental process of Software development commonly used with Agile Software Development. Especially, Scrum will help us to manage the project more efficiently because it is an adaptive process. However, applying the Scrum Methodology should depend on the different situation during the process of project development. It’s a big issue to solve. This article gives an example to elaborate how to manage the project with Scrum.

Introduction

Software development is a complex endeavor. So the most difficult problem is how to handle the complexity through by the science of project management. Many scientists and software engineers raised a great number of methodologies for project management such as Waterfall, UP and Agile. In contrast to the heavy methodologies including Waterfall and UP, Agile is enough flexible to embrace the change, more light to be mastered by project team members, and more focuses on the communication and release of the usable software rapidly. Agile methodologies include eXtreme Programming, Scrum, Feature Driven Development and Crystal etc.

Scrum was raised by Hirotaka Takeuchi and Ikujiro Nonaka in 1986. The skeleton is shown in Figure 1.

The lower circle represents an iteration of development activities that occur one after another. In Scrum, it was called Sprint. Each Sprint is an iteration of 30 consecutive calendar days. The output of each sprint is an increment of product. The upper circle represents the daily inspection that occurs during the sprint, in which the individual team members meet to inspect each others’ activities and make appropriate adaptations.

There are three roles in Scrum including ScrumMaster, Product Owner and Team. The ScrumMaster is responsible for the Scrum process, for teaching Scrum to everyone involved in the project, for implementing Scrum and ensuring that everyone follows Scrum rules and practices. The Product Owner is responsible for representing the interest of stakeholders and creating the project’s initial overall requirement which was called the Product Backlog, for using the Product Backlog to ensure that the most valuable functionality is produces first and built upon. The team is responsible for developing functionality. Teams are self-managing, self-organizing, and cross-functional, and they are responsible for figuring out how to return Product Backlog into an increment of functionality within an iteration and managing their own work to do so.

Problem Statement

Without doubt, Scrum is one of most popular agile methodologies now. It, however, is not easy to apply it to project management. Considering about the following situations please:
1. If the culture of your organization is contradictious with Scrum, and your leader always interrupts you during the process of project development, what should you do?
2. If your team members are not familiar with Scrum, and they don’t understand the heart and rules of Scrum, what should you do?
3. Furthermore if your team members didn’t master the basic skills of Agile developing such as pair programming, Test Driven Development etc, what should you do?
4. If your customers always change their requirement, they are not clear what they want even, what should you do?

Our Solution

In fact, we can’t find out the “Silver Bullet” to solve these problems. We know Scrum is an adaptive process. Scrum makes many rules which should be followed, but not hidebound. It’s agile and flexible. It allows us to adjust the way to achieve the goal of project.

The answer to the first question is operating within the culture of the organization. Don’t fight against the culture of your company. If you are ScrumMaster, you’d better walk a fine line between the organization’s need to make changes as quickly as possible and its limited tolerance for change. You can adopt Scrum by starting small. At the same time, you should try your best to persuade your leader to support you. Sometimes your leader will build the bridge between the agile world and non-agile for you. Of course, it needs change, but these changes must be culturally acceptable. If not, you must acquiesce. The ScrumMaster is a sheepdog of the team, and his job is to protect the team from impediments during the Sprint. Remember that the precondition of which everything is going on well is that the sheepdog cannot be dead. After all, Scrum is the art of the possible.

Right, we hope our team members are all software craftsman so that everything is Ok. Unfortunately, the real world is not as good as that we expect. In fact, the situation in which most of team members are all apprentices is more common. It is true that it is difficult to hire the experienced software engineer in this industry. So the problem we must solve is how to train them. We should draw up a training plan. Before it, we must understand the skill set of everybody. We need to assign the mentors to the fresh guys. Of course, the best way of training is practice. We should assign the task to them according to their ability. At the same time, we have to add the task duration because they are not familiar with the related skills. Besides, Pair programming is a good way to handle it.

The great character of Scrum is enough flexible to embrace the change. Scrum is an iterative and incremental process. The iteration is very short (30 days) so that we can change our plan in time. The incremental development will provide the good policy to submit the release rapidly. The increment product can give our customers confidence. And the customers can understand the difference between what they want and what we provide though by the running software. Scrum emphasis on the communication between the team and customers. Product Owner of Scrum is responsible for communicating with the customers and creating the product backlog. In case the customers changed their requirements, the Product Owner will discuss with ScrumMaster and Team. If the change is acceptable, it is added into the product backlog. If the change is within the sprint which the team is developing, the sprint has to halt, and re-open the new sprint. Beside, the daily scrum will help each team member understand the current statue of the project, and the sprint review meeting will show the result of the sprint to the customers in order to get the feedback from the customers, the sprint retrospection meeting will prompt the Scrum process framework and practices.

Evidence that the Solution Works

Now we complete the first sprint of the project on time. In a month, we went through the whole lifecycle of the software development from the requirement analysis to designing, coding and testing. Each member is familiar with the Scrum gradually. Everything is going on well such as Daily Scrum, Team Work and Sprint Development. In the end of this sprint, we submit the increment product to our customers and get the feedback from the customers. The most important achievement is that our customers approve our approach to develop the product.

Competitive Approaches

We don’t follow the rule of Agile Methodology strictly. For instance, most of team members are accustomed to the TDD (Test Driven Development), so we adopt the traditional way to design and develop the software such as Use Case Driven Development instead of TDD. But we require everybody must write the test case for classes and components. We organize the pair programming group to prompt each other.

Because our customers are off-site, so we require our Product Owner must be in-site and cooperate with them in full time. We create the communication schedule for the customers to understand the customers’ requirement. The Product Owner is empowered to handle everything with requirement.

Especially, the ScrumMaster of our project protects the team from the rest of the non-agile world. We get the enough resources and backup. For example, we have our own agile coach to direct how to apply the Scrum to our project. He can help us to solve the key problem when we are confused of Scrum Methodology.

Current Status

The project is going on well. The first sprint is very successful. Team members are all confidence. They regard the Scrum as the effective and enjoyable process. The customers are satisfied with our process. Most of risks had already solved because we emphasis on them and add them as the tasks into the sprint backlog.

Next Steps

Next month, we are going to hold the Sprint retrospective meeting to find out the existed problems in the first sprint. Then we will create the backlog for next sprint. In this sprint, we will develop the most important domain module and let it workable.

Conclusions

Scrum is an excellent agile methodology to release the software product rapidly and correctly. It gives all team members the new management responsibilities. The process of the project management is visible and controllable. The ScrumMaster and Product Owner don’t need to write the redundant documents and draw up the unrealistic project plan. The team members become more active due to self-organizing and self-managing.

References
1. Agile Project Management with Scrum, Ken Schwaber
2. Software Craftsmanship, Pete McBreen
3. Applying UML And Patterns, Craig Larman

Co-author: Zeng Li, Zhang Yi