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1
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So now let's talk about a specific agile method, which
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is also one of the first ones, extreme programming, also called
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XP. And to introduce XP, I'm going to start with
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a quote. The quote says XP is a lightweight methodology for
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small to medium sized teams developing software in the face
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of vague or rapidly-changing requirements. And this is a quote from
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Kent Beck the American Software Engineer that created extreme programming.
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And by the way Beck was one of the original 17
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developers who signed the manifesto in 2001. And as you can see
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we are still talking about the methodology. So we are not just
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talking about going out and just start writing software. There are principles.
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And there are practices that we need to follow, but we're going
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to do it in a much more agile, and a much more
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flexible ways than we did for our software processes. And also note
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that the vague and rapidly changing
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requirements are explicitly mentioned, because this
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is really one of the important parts about all of this agile methodologies.
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so what is XP? XP is a. Lightweight. Humanistic.
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Discipline. Of software development. It is lightweight because it doesn't
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overburden the developers with an invasive process. So process
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is kept to a minimum. It's humanistic because as we
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said, it's centered on people. People, developers, customers, are
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at the center of the process. It's a discipline, as
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we said, it includes practices that we to Follow.
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And finally, is of course about software development. Software development
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is a key point of the whole method. In XP, developing
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is like driving, imagine having a road, a wind road, we need
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to able to drive our car down the road, take the
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abrupt turns, react promptly to changes, for example obstacles on the road.
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So, in a nutshell, change is the only constant. Eyes always
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have to be on the road and it's about steering and not
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pointing, and XP is trying to do the same thing, while creating
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softer systems. In XP we need to adopt a mentality of sufficiency,
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what does that mean? How would you program if you had all
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the time in the world? No time constraints at all, you will probably
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write tests instead of skipping them, because there's no more resources. You
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will probably restructure your code often,
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because you see opportunities to improve it,
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and you will take them. And you will probably talk to fellow
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programmers and with the customer, interact with them, and this is actually the
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kind of mentality that XP is trying to promote and agile processes
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in general. And we will see that the following some of the practices
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that XP is advocating, you can actually achieve these goals and you can
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actually behave in this way. And the
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development process is going to benefit overall.
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