XP Basics
  • Four Variables: Cost, Time, Quality, Scope

  • Change is certain: Integrate in the Process

  • Four Values: Communication, Simplicity, Feedback, Courage

  • 12 Practices: XP HOW-TO

Notes:

Increase cost and you can do a bit more. Pouring money into a project won't solve the problem. I've been on two "infinitely funded" projects and both were utter disasters. Money does corrupt.

Time is a critical factor. Increase time and you can definitely improve quality and scope. You can also reduce cost a bit by reducing the number of people.

Quality isn't a control variable in most projects. The smaller the project, the easier it is to sacrifice quality.

Scope is the primary control. If you reduce scope, you can increase quality, reduce time and cost. XP is primarily about controlling scope.

You can't change change. It's hear to stay. Everything piece of matter is in constant motion. We can't achieve absolute zero and even if we did, what good would it do? We couldn't look at it, because we would be introducing it.

XP integrates change into the software development process. You will change your code, so write unit tests to make sure you don't break anything. The customer will change her mind, so don't plan too far in advance.

The four values of XP are common sense. We have to fight our ingrained tendencies to be individualists. I'll go over them individually in the next few slides.

The XPHOW-TO are the twelve practices. They are easy to follow. You don't have to integrate them all at once. The more you do, the more success you'll have. The practices are common sense to those of us who've been programming a few years. Most programmers will disagree with one or two, not necessarily the same one or two, however.