Re: [FR-devel] GUI Links and Morphic

[Ron Jeffries]

Around Friday, January 25, 2002, 1:48:30 AM, Horacio Lopez wrote:

> If you don't mind, I will take this opportunity to ask you if you could
> possibly point us to some XP resources on the web.

The best intro to XP on the web is Don Wells' site (it pains me to say
this of course) at xxx.extremeprogramming.org.

There's lots of cool stuff on my site as well, of course. But Don's
intro is great.

I am also fond of my conceptual intro at
http://www.xprogramming.com/xpmag/whatisxp.htm .

> In special  if there's some documentation available on Project Planning,
> and some XP insight on when you need to plan more, if you haven't
> planned well enough, or you are overplanning to much.

What has been going on here is not planning. It's more like analysis
or theorizing about features we might want. It can get wasteful but I
personally tolerate a lot of time spent in this area.

In XP, planning comes in two forms: release planning, where the
Customer (a ROLE, see below) looks at all the features to be built,
(we call them stories) and figures out approximately what will be in
the next release. (It's approximate because XP planning basically
works on detailed control of project scope to meet a date.)

The other plan is the iteration plan, where the Customer (wait for it,
it's coming) decides what the work is that will be done in the next
iteration. This is a selection of the stories to be done based on (a)
the value of the the story to the project, as currently understood by
the Customer, (b) the cost of the story to implement, as currently
understood by the Programmers, and (c) the number/cost of stories that
the team has developed in previous iterations.

XP iterations are about two weeks long: the customer asks for and the
team signs up to do the work in two-week sized chunks. //There are
/no/ features on an XP project that take longer than one iteration to
implement.// (And, yes, //any// project can be done that way. There
are no features /in the universe/ that cannot be broken down for
implementation in two-week chunks. (Unsupported but thoughtful
assertion.))

Anyway, this planning takes place based on the customer giving the
developers lots of stories, the developers estimate how long it will
take to do each one. (If a story is longer than an iteration, the
customer breaks it into shorter stories.) When all the stories have
estimates, it's time to see what kind of release you can make.

"Customer" in XP is a ROLE. It represents the individual or group that
has the business responsibility to decide what is done and what is
deferred in the development. In open source and other free
developments like this one, it's probably the project owner who makes
the final calls. XP recommends against programmers putting in random
features because they like them, because XP wants to have the control
of the project's spending in the hands of the business people. That
may or may not apply to us here: we have to decide. We probably want
to tolerate more experimentation, but if we are to come out with a
coherent product in finite time, we do need to decide in some
effective way what to do and how to do it.

> Is there documented reference on this in XP practices ?
> (if not web links, maybe dead tree ones)

The best dead tree on the whole process is probably mine, because it
includes details on how to do things. The best dead tree on what XP is
about is Kent's white book, /Explained/. There is a book on planning
but it is probably overkill for us. /Installed/ (mine) includes more
than enough for our purposes, I think.

Overall, there are surely ideas in XP that would be helpful to this or
any project. The project team needs to decide what overall approach it
wants to take and which practices to use.

Ron Jeffries
www.XProgramming.com
Discontinue reading if rash, irritation, redness, or swelling develops.
Especially irritation.