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Comment by sealeck | Hacker News Reader

rm -r

Problem solved

If you mean "rewrite from scratch", believe me, it is the worst thing you can do. I speak from experience, it is tempting but the few times I have done that, a few months later as I get burnt, I could only think of how an idiot who never learn I was.

Legacy code is like that because it went through many bugfixes and addressing weird requirements. Start over and you lose all that history, and it is bound to repeat itself. That weird feature that makes no sense, as it turns out, makes a lot of sense for some users, and that why it has been implemented in the first place. And customers don't care about your new architecture and fancy languages, they want their feature back, otherwise they won't pay.

Another way to look at it is when you asked to maintain a legacy code base, that's because that's software that has been in use for a long time. If it was that bad, it would have been dropped long ago, or maybe even cancelled before it got any use. Respect software that is used in production, many don't reach that stage.

Of course there are exceptions to that rule, but the general idea about rewriting from scratch is: "no" means "no", "maybe" means "no", and "yes" means "maybe".

I'm being like 1000% facetious, and agree that rewrites are bad.

I have been involved in a successful rewrite. It cost billions of dollars and many years when the code wasn't working so the old system was still in use. We also ended up bringing over some old code directly just to get something - anything - functional at all. For many years my boss kept the old version running on his desk because when there was a question that old system was the requirements.

Today we only have to maintain the new system (the old is no longer sold/supported), and the code is a lot better than the old one. However I suspect we could have refactored the old system in place for less time/money and been shipping all the time. Now we have a new system and it works great - but we already have had to do significant refactors because some new requirement came along that didn't fit our nice architecture.

> because some new requirement came along that didn't fit our nice architecture.

This is the thing.

I was doing the event section of the website and it was the event. I mean, it was preposterous to even think of running multiple events. Fast forward a few years, the company is now many times the size after very rapid growth, has an office in the UK and now runs multiple events. Would you have made an architecture for multiple events back then? YAGNI whispers you not to...

When considering this question, I've designed for things knowing they would come and they never did. I've also designed for situations that did come, but 10 years later we discovered a significant downside that we didn't anticipate and so the seemingly non-elegant hacks would have been better.

> C++

> Not even once

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