Extreme Programming (XP) and scrum differences for agile methods

Agile as a development process, currently used by major companies, agile process specific practices have XP and scrum, it seems that few an article introduce the difference between the two,

Find a foreign language, the insight is very profound, special translation of it.

The original text (DIFFERENCES between SCRUM and EXTREME programming) is in this:

Http://blog.mountaingoatsoftware.com/differences-between-scrum-and-extreme-programming

The author summarizes the following general differences:

One difference: The length of the iteration is different

The iteration length of a sprint for XP is roughly 1-2 weeks, while the iteration length of scrum is typically 2~ 4 weeks.

Difference Two: Whether the requirement is allowed to be modified in the iteration

XP in an iteration, if a user story (which is a requirement) has not yet been implemented, consider replacing it with additional requirements, the principle of which is that the amount of time required to implement is equal. Scrum is not allowed to do this, and once an iteration is completed, no requirement is allowed to be added, and scrum master is strictly not allowed to be disturbed by the development team

Difference three: In the iteration, whether the User story is strictly according to the priority level to implement

XP is a must to adhere to the priority level. But scrum is flexible enough to do this without priority, and the rationale for scrum is that if the solution to a priority problem is delayed by other things and cannot claim the task, then the overall progress is delayed. Another reason is that if the user story ranked by Priority #6和 # #, although the high priority, but if the implementation of the achievement to rely on the # #, you have to prioritize the # #.

District Four: In the process of software implementation, whether strict engineering methods to ensure the progress or quality

Scrum does not prescribe an engineering practice for the entire implementation process of the software. Developers are required to make a conscious commitment, but XP has a strict definition of the entire process approach, requiring the use of TDD, automated testing, pairing programming, simple design, refactoring, etc. to constrain the behavior of the team. Therefore, the original author believes that this, XP approach is worthy of recognition, but the agile into a confusing paradox, because the concept of XP, combined with the agile model, the message expressed to the team is "you are a fully self-managed organization, but you have to achieve TDD, pair programming, ... And so on

It is easy to see that the four differences are obvious: Scrum is very prominent self-orgnization, XP focuses on strong engineering practice constraints

The authors recommend that Scrum be enabled in management mode, and in practice create an XP ("Start with Scrum and then invent your own version of XP") that suits your project team.

Extreme Programming (XP) and scrum differences for agile methods