Прочитайте эти два описания двух разных попыток - включая все пять записей Джеффриза, не поленитесь, чтобы как следует их оценить - сравните, и вы будете знать все, что вам надо знать, об XP и Agile.

Around 1993 I started reading books about Lisp, and I discovered something important: Perl is much more like Lisp than it is like C. If you pick up a good book about Lisp, there will be a section that describes Lisp’s good features. For example, the book Paradigms of Artificial Intelligence Programming, by Peter Norvig, includes a section titled What Makes Lisp Different? that describes seven features of Lisp. Perl shares six of these features; C shares none of them. These are big, important features, features like first-class functions, dynamic access to the symbol table, and automatic storage management.
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Instead of telling you how wonderful Lisp is, I will tell you how wonderful Perl is, and at the end you will not have to know any Lisp, but you will know a lot more about Perl.
Then you can stop writing C programs in Perl. I think that you will find it to be a nice change. Perl is much better at being Perl than it is at being a slow version of C. You will be surprised at what you can get done when you write Perl programs instead of C.

antilamer

I don’t think code should be owned. I don’t think anyone really thinks that. The way it works within Google is that it’s one massive source tree, one root, and one unified build system across all of it. And so anyone can go and change anything. But there are code reviews, and directories have owners, always at least two people, just in case some quits or is on vacation.

To check in you need three conditions met: You need someone to review it and say it looks good. You need to be certified in the language—basically you’ve proven you know the style of this language—called “readability.” And then you also need the approval above from somebody in the owner’s file in that directory. So in the case that you already are an owner of that directory and you have readability in that language, you just need someone to say, “Yeah, it looks good.” And it’s a pretty good system, because there tends to be a minimum of two, up to twenty, thirty owners. Once you work on a code base for a while, someone just adds you to owners. I think it’s a great system.