Why Does Software Rot?
overcomingbias.com
Why Does Software Rot?
1–10 of 81 posts
Re: Why Does Software Rot?
#2Wheres the connection to software rot?
Re: Why Does Software Rot?
#3What does rot even mean, in terms of software?
As far as I can tell, he means "Why is complex software hard to change" which is a reasonable, though fairly easy to answer, question.
Software doesn't rot. New features or refactors screw it up. New needs or technologies may make it obsolete. But it doesn't rot, and people who talk that way are often busy-body rewriters who want to pitch the existing implementations, with all their Chesterton Fences[1], and begin anew.
Re: Why Does Software Rot?
#4What does rot even mean, in terms of software? As far as I can tell, he means "Why is complex software hard to change " which is a reasonable, though fairly easy to answer, question. Software doesn't rot. New features or refactors screw it up. New needs or technologies may make it obsolete. But it doesn't rot, and people who talk that way are often busy-body rewriters who want to pitch the existing implementations, w…
It rots in the sense that it becomes harder to change (or fix) over time, even if the code stays the same. This happens via loss of institutional knowledge as people forget how it works, loss of knowledge of the technologies used as they're replaced, etc. It's not just the complexity. Old code is usually harder to change than new code, even if they're equally complex.
Re: Why Does Software Rot?
#5What does rot even mean, in terms of software? As far as I can tell, he means "Why is complex software hard to change " which is a reasonable, though fairly easy to answer, question. Software doesn't rot. New features or refactors screw it up. New needs or technologies may make it obsolete. But it doesn't rot, and people who talk that way are often busy-body rewriters who want to pitch the existing implementations, w…
Changes in the environment screw it up, too. As an obvious case, if your software is screen-scraping a website and the website's layout changes, your software's just rotted even though your code hasn't changed one bit.
Another example is software which interfaces with hardware: Swapping one specific piece of hardware out for "the same" hardware made by a different manufacturer can cause rot, because "the same" hardware isn't necessarily the same in every respect. If your software tickles it the right way, it can expose differences which can cause your software to fail in new and exciting ways. Nothing changed, yet everything's different.
As you expand the universe of things your code has to interact with, this kind of change becomes inevitable. As always, the more points of attachment, the more potential for future pain.
Re: Why Does Software Rot?
#6Three reasons:
1. The code is the same but the people using it forget / never knew the reasons it was built that way - and so it looks rotten for the job
2. Because requirements change and people try to make the old code do new things without cleaning up / refactoring correctly - so it now does neither job well, and looks rotten.
3. Because the environment / platform changes, the FTP server is moved to a new data center and the timeouts kill the jobs etc. It looks rotten.
"Rot" more accurately is just not keeping the code inside the code base up with entropy outside the code base
Re: Why Does Software Rot?
#7What does rot even mean, in terms of software? As far as I can tell, he means "Why is complex software hard to change " which is a reasonable, though fairly easy to answer, question. Software doesn't rot. New features or refactors screw it up. New needs or technologies may make it obsolete. But it doesn't rot, and people who talk that way are often busy-body rewriters who want to pitch the existing implementations, w…
It rots in the sense that it becomes harder to change (or fix) over time, even if the code stays the same. This happens via loss of institutional knowledge as people forget how it works, loss of knowledge of the technologies used as they're replaced, etc. It's not just the complexity. Old code is usually harder to change than new code, even if they're equally complex.
That isn't rot. The metaphor doesn't make any sense.
Software literally does not change. Except for the occasional cosmic ray, I can think of few things less appropriate to apply the term "rot" to.
Re: Why Does Software Rot?
#8Three reasons: 1. The code is the same but the people using it forget / never knew the reasons it was built that way - and so it looks rotten for the job 2. Because requirements change and people try to make the old code do new things without cleaning up / refactoring correctly - so it now does neither job well, and looks rotten. 3. Because the environment / platform changes, the FTP server is moved to a new data cen…
Or when the operating system or build tools change or are no longer available. Your code hasn't changed and suddenly it no longer compiles.
Re: Why Does Software Rot?
#9Software rots if you can no longer set up the exact tool chain and environment (compiler, build tool, OS version, external database, etc) required to build and run it. Even interpreted languages suffer from this problem as features are subtlely changed - by design or accident. It doesn't matter if your project is using an ancient version of VC++ or a two year old version of NodeJS. If it doesn't keep up with the latest releases of the tools then it's already got one foot in the grave.
Re: Why Does Software Rot?
#10Unless your sandboxed in a self contained hardware and software environment (such as an embedded system) you will eventually be screwed. (rot sounds like a gradual degradation its generally not in my position)
Standards changes and OS Updates are the biggest culprit; The Vista update broke a couple of my old programs (written for Windows 95) due to the user access control changes, another was broke due to the fact it interfaced to a piece of hardware on the parallel port and the parallel port and the manufacturer went the way of the dodo.
I have seen a stand-alone DOS 6 program running a machine at a factory. The PC has been replaced three times now is only a few years old but the operator says it still does the job, I also have a 8051 powered clock I built in 1987 that still happily ticks along if I plug it in.