Andrew Hunt and David Thomas have a written a great book called The Pragmatic Programmer. This book covers so much great stuff!  Most of the time, while was reading it, I found myself sitting with the jaw against my chest in astonishment of how clearly Andrew and David pinpoints problems and recommendations in software development. I think all seasoned developers would have the same feeling since the problems Andrew and David writes about are well-known, but not very easy ones to actually pinpoint and describe.

As a side note, at the Øredev conference recently, I saw Andy Hunt giving an excellent key note speech opening up the conference. There was quite a number of fascinating subjects he talked about and I hope to be blogging on some thoughts on these subjects in the near future.

Anyway, in the book, the writers bring up a term called software entropy as a force very difficult to avoid for developers. When I first heard of entropy it was actually in chemistry class many years ago. An explosion is an excellent example of a chemical reaction that renders a very high order of entropy. I.e. the amount of disorder of atoms in the explosion is very high in the beginning but rapidly goes back to a low level of entropy. Naturally, this is due to the high amount of energy that sets the atoms in motion.

There is a striking similarity with software entropy I think. When things are heating up in a development team and we are as busy little bees to meet a deadline, entropy is bound to be high. Or at least the risk is very high that the entropy gets high. As a cause of this, Murphy’s Law might appear out of nowhere which seems to be a result of just pure bad luck. But often it is the just the result of high entropy, i.e. the disorder tends to get high as we get stressed out and several accidents happens in a short amount of time.

The writers go on with an analogy to city buildings that are of very different quality in different neighborhoods; some buildings being very clean and neat while others in another area are in a very poor state. This is the effect of “a broken window”. If one window gets broken and it does not get fixed immediately, then soon another broken window will appear; and yet another and so on. Soon the neighborhood will look like skid row and criminality increases drastically.

That this is so, even Swedish governments have concluded. I recently saw a news program stating this very fact. And in the local news paper the same very fact got stated about a neighborhood not too far from where I lived. A whole city block is going to be torn down and rebuild and as a result, criminality is sure to drop it was stated. Well, good!

I think there is an absolute truth in this and that it can be explained with our pride. If you are not proud over the neighborhood you live in, you are not going to respect either the buildings or the people that live in them. But if you feel pride over a good, esthetic environment that surrounds you, you take more care of it.

As for software development, we have the same situation Andrew and Thomas states. If you don’t feel proud over the code that is produced in the project and honor its design, the software will begin to rot. If this happens, sooner or later you probably are going to have to throw it all away and redo the whole thing from scratch.

So, as the authors of The Pragmatic Programmer so wise fully states: don’t live with broken windows. Anticipating that the design of the software is a good one, follow it instead of doing small hacks in order to save time. That time you save may very well be 10 times the time lost further down the road when someone is trying to get the once upon a time nice design to work again as it should be.

I know: Software is never perfect and this is not what the authors, neither I, are saying. However there is a great difference between delivering good enough software and doing “hacks” to the system all the time.

Unfortunately there is a driving force that often makes these hacks necessary: the critical deadline of a promise made to somewhere by somebody by someone... But the underlying reason for this is often due to a crappy or not existing project methodology which is a subject that I won’t dig into in this blog post. However, this spring I probably will write a lot more about this.