[aidenn0]

In Joel's defense, we don't know that gecko is better than X years of incremental changes to Netscape 4.

One of the big issues with software engineering advice is that it is really hard to find apples-to-apples comparisons for outcomes.

[mjw1007]

True.

I think we can say that Gecko ended up technically better than incremental changes to Internet Explorer, which I think was starting off from a more maintainable codebase than Netscape 4. That's hardly conclusive but it's some evidence.

[aidenn0]

Indeed. My intuition based nothing other than my subjective experience is that there are times that throwing away the code is the correct decision, but they are a rounding error compared to the times that people want to throw away the code, so to a first order of approximation "never start over from scratch" is correct.

Simply shifting the burden of proof to the "rewrite" side is usually sufficient. Where I currently work a rewrite request is not answered with "no" but "show me the data." 90% of the time the requester doesn't even try to gather data, the other 10% of the time results in some useful metrics about a component that everyone agrees needs some TLC, whatever the final decision.

[lucideer]

> we can say that Gecko ended up technically better than incremental changes to Internet Explorer

> ...

> That's hardly conclusive but it's some evidence.

Given Internet Explorer's monopoly position, and consequent disincentive to compete, it's not really the best comparison.

Compare to something like Opera Presto, a codebase that - while younger than Netscape - predates Internet Explorer, which underwent incremental changes while remaining in a minority market position. It was killed by market forces, but I doubt anyone would contest it was a badly put together piece of software in the end.

Konqueror is another example. It's not quite as compelling, as KHTML itself has fared less well than its forks, Safari WebKit has never exactly been a leader in engine advancement, and Chrome's innovations, while incremental, were largely built on a scratch-rewrite-and-launch-all-at-once of one component (V8). However KHTML/Webkit/Blink is still pretty much an incremental rewrite success story.

[iopq]

I actually used Opera because it allowed me to stop websites from hijacking my browser. No capturing my right click or any of this silly bullshit. The exact UI/features I want. Opera 6-12 were good times.

[olavk]

Yeah but Microsoft let IE stagnate for half a decade after it had achieved dominance. There were 5 years between IE 6 and IE 7. If MS hadn't disbanded the IE team but had kept up the pace of incremental development, I very much doubt Mozilla would have ever been able to catch up again.

I would say Joels point still holds in the general case where you you can't count on competitors to just stop developing their product until you have achieved parity again.

[mjw1007]

IE6 was released about the same time as Mozilla 0.9.3. I think Mozilla was already ahead in technical terms at that point.

Certainly it had better CSS support, and on my machine it crashed less.

The important difference was a matter of support for "official" standards against support for "best viewed in Internet Explorer" sites.

[pawelk]

And, as far as I know, Microsoft has developed Edge from scratch after all. The years of incremental updates to IE are now maintained for legacy support.

[robin_reala]

That’s incorrect. Edge is still Trident, but they took the opportunity of a change in name to rip out all of the old backwards-compatibility layers and leave just the modern stuff.

[Jweb_Guru]

> In Joel's defense, we don't know that gecko is better than X years of incremental changes to Netscape 4.

Yes, we do, as does anyone who was following browsers at the time. They tried to incrementally improve Netscape 4 and it was a disaster.