Comments on: Sometimes you are truly better off starting from scratch

By: Tim

Tim — Fri, 10 Aug 2007 19:04:15 +0000

I think the value of writing your own solution, even if it’s inspired by that of others, is that you as the developer really internalizes the solution (your #5 above.) This shows itself, and usually pays huge dividends, when some of your other points come into play, namely looking for bugs later, trying to add a new feature or scaling the app. One other point is that an existing implementation often isn’t written in the same style as yours, or that of your company (therefore making maintenance on it later again more difficult.)
There are certainly places where off-the-shelf or borrowed code can pay-off in a big way, but in a strategic area that I’m committing to long-term, I generally prefer the developers that are going to have to maintain the code to have written it.

By: Avi Flax

Avi Flax — Fri, 10 Aug 2007 18:08:01 +0000

Chris, that’s an interesting example. Sure, the new codebase that Netscape developed turned out to be quite good, and quite valuable – but it didn’t save the company.
Also, I’m not sure the question of “rewrite or refine?” is directly applicable to Joel’s post, which is more about “use an existing implementation or roll your own?”

By: Chris D

Chris D — Tue, 07 Aug 2007 03:20:55 +0000

Great post, Joel. I agree completely, especially when it comes to an area like web development, where codebases are usually not monolithic monstrosities.
I’d also like to point out a place where Joel Spolsky disagreed with you, and later showed himself to be a little off the mark: in “Things You Should Never Do, Part I” (written April 6, 2000), he tears into Netscape for rewriting it’s browser after netscape 4.75 – calling it the ‘single worst strategic mistake’ a company could make.
Of course, we know that after a while, the mozilla suite became pared down into one of the best browsers around, Firefox, and although I can’t see alternate realities, I doubt it would be as popular if they had stuck with the Netscape 4.75 codebase and built off of it.