When Kent Beck was brought on to improve the Chrysler Comprehensive Compensation (C3) program in the mid-90s, XP was used for the first time on the project. The team added Ron Jeffries and others. People who worked on this project wrote several books that spread knowledge about and adapted the XP methodology. Agile software development frameworks like XP enable development teams to produce high-quality software. Taking traditional programming practices to extremes inspired this methodology’s name. This model was developed to create a lightweight process model. It is more specific to XP than any other agile framework. Software is developed according to customer requirements. This software development process is agile and involves many releases in a short period. Each step improves software quality.
Programmers and customers come together to work on a project jointly. As a team-oriented project, all developers must complete the project successfully, not just the boss or owner. XP works best in small teams. In most cases, 12-14 people are involved. Additionally, it facilitates early user and customer involvement, reducing communication gaps. Furthermore, it has a social focus. Values are at the heart of the XP methodology. These values are Communication, Simplicity, Feedback, Courage, and Respect.
Kent Beck summarizes XP’s core values in this statement: Do more of what works and less of what doesn’t. Beck and Fowler outline XP as having a clear division between business and technical people. The business determines the content and sequence of system functions. Technical responsibilities include determining how and when the system will be built. In addition, these two sets of decisions cannot be made separately from one another, as each influences the other significantly.
The following values are critical: Understanding and implementing customer needs is the essence of software development. Interaction between team members is essential, and communication is promoted through drawing tools. Planning first makes things simple. It helps developers focus and avoid unnecessary tasks. Moreover, it emphasizes focusing on the present rather than predicting the future. System maintenance and improvement should also be simple. Feedback from previous works can help identify areas for improvement and simplify the design. There’s much fear when something you’re working on doesn’t work. Customers and programmers should respect each other in a project and accept feedback to succeed.
Core practice number 1: The Planning Game. To accelerate business value production, business and development work together. The planning game has various levels, but the basic rules remain the same: The business generates a list of features it wants the system to have. The requirements for each feature are outlined in a User Story, a short description of what the feature does. 4×6 cards are typically used to write user stories. Each story is estimated according to the effort it will require and the amount can be accomplished in a specific period. In the next step, the business decides which stories to implement in what order, when to release the system, and how often.
Core practice number 2: Small releases. The XP approach to minor releases involves two crucial features: First, the team strives to release running, tested software every iteration, delivering business value determined by the customer. The software can be used for any purpose, including evaluation and release to end users. Every iteration must conclude with the software being visible and handed over to the customer. XP teams also release software to end users.
Core practice number 3: Simple design. With XP, the most straightforward design is used to accomplish the task. Make only the changes needed to meet today’s requirements because tomorrow’s requirements will change. XP does not think of design as a one-time exercise but rather as something that needs to be done continuously. A release plan and an iteration plan implement design steps, quick design sessions, and design revisions through refactoring throughout the project.
Core practice number 4: Metaphors. During extreme programming, teams develop a shared understanding of the program’s functions, which is called a “metaphor.” An effective metaphor evocatively describes how a program works. In XP teams, everyone uses the same names to ensure they know how the system works. They also know where to find the functionality they need or where to put the functionality they’re adding.
Core practice number 5: Continuous Testing. Extreme programming teams focus on software validation. Tests are written before the code is written, and then the code is coded to meet the requirements reflected in the tests. Customers are responsible for acceptance tests to ensure they receive the required features.
