What are the core practices of extreme programming?

Over the time the extreme programming has proved itself to be a great helping hand as an agile practice in improving the overall quality and productivity of the software products according to the ever changing requirements of the customer.
Being an agile practice it frequently releases software products with the short development cycle which is achieved through time boxing. During the whole process several check points are introduced in to the development cycle where the new customer requirements can be easily incorporated in to the software system.

Elements of Extreme Programming

There are several elements of the extreme programming like:
1. Pair programming
2. Extensive code review
3. Unit testing
4. Maintain simplicity and clarity of the code
5. Providing a flat management structure and so on.

Values of Extreme Programming

The extreme programming is guided by values, rules and principles! There are 5 values namely:
1. Communication
2. Simplicity
3. Feedback
4. Courage
5. Respect

Principles of Extreme Programming

The rules of the extreme programming govern its all time activities. Three basic principles have been defined for the extreme programming as mentioned below:
1. Feedback
2. Assuming simplicity
3. Embracing change

core Practices of Extreme Programming

The extreme programming is said to be composed of 12 practices which is what we going to discuss in this article. The 12 practices have been grouped into sets of four:

1. Fine Scale Feedback: This area involves 4 following practices:
(a) Programming in pairs: This agile practice involves 2 programmers working side by side one of which is a driver and other is an observer. The driver is suppose to type in the code while the observer holds the duty to review each line of the code typed.

(b) Planning game: This is the most important practice in the extreme programming. The game here is the name given to a meeting that is held once for every iteration of the development process with the purpose of guiding the product in to delivery. It has 2 parts:
- Release planning: It has 3 phases:
    + Exploration phase
    + Commitment phase
    + Steering phase
- Iteration planning: It too has got the same phases as the release planning.

(c) Test driven development or TDD: This is another agile practice relying on the iterative and incremental approach and refactoring of the code for improving its overall design.

(d) Whole team: Extreme programming forces the need of the customer availability at all the times for questions.

2. Continuous Process: This process is constituted of the following 3 practices:

(a) Continuous integration: In extreme programming it is required that only the latest version of the software system or application is worked up on.  The current version of the software that is available with the different team members must be uploaded to the code repository in every few hours since this avoids delays in the project cycle.

(b) Design improvement or re-factoring of the code: Since only the required functionalities are implemented, this may cause the system to hang. This may require dual maintenance then. In such cases changes in one part of the program affect the other parts of the code. At such times the refactoring of the code is needed.

(c) Small releases: The software is delivered via the frequent releases of the live functionalities. With these small releases the customers gains the confident about the progress of the development and the concept of the “whole team” is also maintained. The customer as well is able to come up with the suggestions regarding the development of the software.

3. Shared Understanding: This involves the following 4 practices:
(a) Coding standards
(b) Collective code ownership
(c) System metaphor
(d) Simple design

4. Programmer Welfare: It involves development at a “sustainable pace”.