Hacker News Reader

Comment by lmm | Hacker News Reader

You can write a million lines of code that do arbitrarily little, particularly if you're following poor development practices. I've seen a million-line codebase that could have been replaced with 10k lines of python. Depending on what functionality they actually need and how much they need the developers, Acme could well be making the right decision.

View on HN

You know why you can do that? Because you have hindsight. You see exactly where the business went.

And this is the same damn trap all neophyte developers fall into. "Let's rewrite!"

Once that first wave of business requests and demands comes along, your precious sandcastle will crumble. Because the business team is fickle. And they stick you with deadlines. And then, mid-deadline, they change their mind. Or are forced to go a different direction because some shit government law is passed that requires you to broadcast your service requests with encrypted messages tied to pigeons (because, realistically, that's how the government does APIs).

Here on the internet where everything is made up and the points don't matter, you can get away with rewrites. Agile not working for you? Let me introduce you to the CADT model (http://www.jwz.org/doc/cadt.html).

All rewrites become tomorrow's bug-infested legacy ghettos.

You're usually correct. But a great developer is one who can spot the cases where the patterns don't apply. There are cases where the legacy code is so bad that it's better to throw it away, and there are rewrites that work out well (I've been part of one of them).

(Don't listen to JWZ, at least on business/strategy. His employers don't exactly have a great history of success on that front)

I think this is the key. I have this big honking system that nobody really understands. We need a system to do X. please implement X is way easier than the whole, rewrite a million lines problem.

What is also key is understanding that this is almost never the way that happens.

It goes more like this:

We have this big honking system that nobody really understands. We need a system that does X (where X is the list of features we think the other system does that are critical. X is subject to change as we discover other features to add and features that actually weren't necessary.) Please implement X this way.

And that can easily become an exercise in extreme frustration.

In my experience, the reason they will not even consider "Please implement X" as an option is because they see ANY additional effort as more expensive. They figure taking the existing code and producing a new system that EXACTLY duplicates the functionality will guarantee controlled costs.

They're wrong of course, but this is how it is done, at least in government contracting circles. I have literally seen developers required to get out a RULER and measure user interfaces as they appear on one screen so that they can exactly duplicate them on newer higher-dpi screens without changing the appearance or functionality whatsoever.

Everyone presumes the million-line system is one which could be implemented much more simply... there are some systems, however, that need those million lines. Rewriting one of those in a new language is a whole different level of nightmare. Especially when the requirements are 'make it work like the old system' and nothing else, and the requirements for the old system are 30 years old and not even close to portraying the system as it stands currently... But hey, to avoid 'being the next healthcare.gov', political types will push anything out the door and just shoot anyone who points out problems in the back.

Reply on news.ycombinator.com