eXtreme Programming: An Introductory Guide for Beginners

Customer satisfaction should be at the heart of every company's strategy. And to ensure that it is met, it is essential to include them throughout the project implementation process and to collaborate with them to take into account their requirements and changes. All the agile methodologies apply this principle. This is the case of the eXtreme Programming or XP method, which ensures that the product or service delivered precisely meets the needs of the customer.

By following this method, your project team can thus be reactive to changes that occur at any time during the project life cycle.

But why eXtreme Programming? Because this method is considered to be the most extreme implementation of the agile approach.

Definition

The first project carried out using the eXtreme Programming method dates from 6 March 1996. Kent Beck, Ward Cunningham and Ron Jeffries developed and refined the method by working on the “C3” project to calculate remuneration at the American company Chrysler. The method was officially published in October 1999 in the book Extreme Programming Explained by Kent Beck.

Originally, the XP method was created for the IT sector and software development. But since then, it has enabled the success of numerous projects in companies of different sizes and sectors around the world.

The principles of eXtreme Programming are those of the agile approach, but taken to the extreme. This method promotes collaboration between all the actors in a project: members of the project team, customers, suppliers, service providers, etc. It is based on iterative processes, i.e. short cycles that include tests, exchanges with the customer and continuous deliveries. In this way, the project team can quickly detect and eliminate errors, and they can immediately implement the changes requested by the customer.

Values

The XP method is based on five fundamental values:

• Communication : essential to the success of the project, it makes it possible to quickly detect problems and to solve them as soon as possible. It's about communication between the members of the project team and with the client. Face-to-face communication should be preferred.
• Simplicity : “simplicity is the secret of success.” André RochetteIn the XP method, we favor simplicity and we only develop what is necessary and required at the moment, nothing more. No need to try to anticipate, or to get lost in ancillary considerations. It will always be possible to change the product later.
• Feedback : Regular product tests, short cycles and frequent deliveries make it possible to detect errors, to have quick feedback and thus to continue to improve it. It is essential that the project team and the customer share their feedback as often as possible so that every change request is taken into account immediately.
• Courage : changes require courage. Indeed, it takes courage to review what exists but does not work, and recreate something new, adopt a new technique, or completely change the organization of the project. It also means having the courage not to give up, being persistent to succeed.
• Respect : this value includes respect for others as well as self-respect. It is essential to respect the people you work with, whether they are part of the project team or not. Mutual respect contributes to the good atmosphere within the team and to its performance.

How does it work?

The five values of XP are divided into thirteen practices that build on each other.

• Customer on site : to ensure quick and regular feedback between the client and the project team, the client must be represented on site throughout the duration of the project. This representative is available to answer the team's questions, offer ideas, and define priorities.
• Planning game (or planning poker) : this is a meeting organized at the start of each new iteration. The team and the client discuss the work done, share their feedback and discuss the next tasks to be completed. These are then assigned to the members of the project team.
• Continuous integration : the functionalities are integrated into the project as and when they are implemented. In this way, we avoid an overload of work and stress to integrate everything into the project just before delivery. Tests are essential: as soon as they are positive, the iteration is considered complete.
• Small deliveries : regular deliveries allow for more frequent customer feedback and the detection of possible errors more quickly to correct them in the next iteration.
• Sustainable pace : no one has to work overtime. If this is the case, review the schedule. A tired employee will perform less well and may make more mistakes.
• Functional tests : these tests make it possible to check the progress of the project. If they are validated, the iteration is complete.
• Unit tests : Each feature is tested to ensure that it will work as expected. It is verified with this same test throughout the duration of the project. This type of test, which is often automatic, makes it possible to identify errors.
• Simple design : we avoid complications, we stay simple and we get to the point by taking into account the current needs of the customer, without anticipating anything. Each deliverable may evolve in future iterations.
• Use of metaphors : the project team and the client must speak the same language to understand each other, and to understand how the project and the final product work. Simple terms and metaphors can be used.
• Refactoring (or redesign of the project) : the project and its functionalities are constantly being improved to avoid mistakes and provide an impeccable final product.
• Collective ownership of the project : the responsibility for the project is shared by the entire team. Each collaborator can improve functionalities, even those that they have not worked on.
• Naming convention : make everyone's work easier by using the same terms for everything related to the project.
• Working in pairs : two collaborators are assigned to each task, a pilot and a co-pilot. This way of working makes it possible to avoid mistakes and to provide better deliverables the first time.

Conclusion

The XP method applies agile principles to the extreme. Simplicity, responsiveness of the project team, regular feedback and integration of changes are the bases of this method.

For it to work, it is essential that all the actors in the project collaborate together, and especially that the client is fully involved in the project.