The Problem: Rewrite Mania

The Problem: Rewrite Mania

I have been noticing a certain trend in software toward rewriting successful tools and standards. It seems that programmers always have the urge to make things better, which is perfectly understandable - after all, this is the primary trait of the engineer's mind (although I also think that artistic creativity also enters in the mix). Why should things stay static? Surely progress is good, and if we just stayed in the same place, using the same versions of tools without improvement, then things would deteriorate and generally get pretty boring.

That's all very true, but what I am seeing is that in many cases we have tools which truly are "good enough" for what they are designed to do - TCP/IP allows us to build giant, interconnected networks, Apache lets us build flexible web servers, Perl lets us write incomprehensibly obfuscated code(!)... well, point being, these things work. Really, outstandingly well. They are "good enough", and moreover they are used everywhere. So all's well and good, right? Well, not exactly. The programmers add little bits and pieces here and there, fix lots of bugs, and over time the code starts to look distinctly messy - and with the insights gained from this "first version" of the application (I don't mean V1.0, but rather the overall codebase) the developers start to think about how it could be "done right". You know, now they know how they should have done it.

Fired with new zeal and enthusiasm, the developers embark on a grand rewrite project, which will throw out all the old, stale, horrible, nasty untidy code, and construct reams of brand new, clean, designed, and, uh, buggy, incompatible, untested code. Oh well, it'll be worth it ... right? So the new version will break some things that worked with the old version - the benefits from the changes far outweigh a loss of backward compatibility. In their minds, the developers are more focused on the cool aspects of the new version than they are on the fact that in the real world, millions of people are still using the old version.

Eventually, then, the new version comes out, to grand fanfare. And a few people download it, try it... and it doesn't quite work. This is perfectly normal, these things need time. So all the people who are running large production systems with the old version just back off for a while until the new version has been tested properly by, uh, someone else. Thing is, nobody wants to use their own production system to test the new version, particularly when the new version is incompatible with the old version and requires config changes which would be a pain to change back to the old version when the new version breaks!

So what do we end up with? Two versions. The old one (which everyone uses) and the new one (which some people use, but is acknowledged to be not as reliable as the old one). Perhaps over time the new version becomes dominant, perhaps not... the