XP Loops

Objectives:

Introductory overview of Extreme Programming, as one concrete example of an agile methodology.

Presenters : Vera Peeters and Pascal Van Cauwenberghe
Contents:

An XP team behaves in an iterative and incremental way. We describe this behaviour in 3 increments, 3 endless loops that the team goes through. The outer loop is the release loop, which interacts with the outer world, and which will let a predefined amount of working quality software pop out of the team regularly. The middle loop is the team loop, which handles day to day team activities. The inner loop is the coding loop, where two programmers, sitting side by side, produce a unit of tested code.

Extreme Programming is a methodology that is very simply to explain. Through the focus on the details, a bigger picture will emerge, where you will be able to see the principles and the values. Each of the practices of Extreme Programming will be discussed briefly and illustrated with examples from the presenters' experience. Long enough to give you a good global overview, but only just long enough to leave you with a lot of questions.

The loops indicate several things:

• Each loop has a typical duration: e.g. 1 month/1 day/1 hour
• Each loop has a "span of control": team+customer/team/individual or pair. If you want to make changes in one of the loops, you have to agree with everybody involved in the loop
• Each loop contains a set of strongly related practices. You do not have to implement XP in one go, you can do it incrementally. But you will have to tackle most of the practices in one loop at the same time.
• The loops give you four intervention points: coding/teamwork/planning/interaction with the rest of the world. So, when improving your process, concentrate on the loop where the bottleneck is.

Process & Timetable:

• Intro
• Outer Loop: Planning
• Middle Loop: Team
• Inner Loop: Code
• The agile principles implemented by XP
• Other agile methods
• Questions (and answers if we have them)