Do the simplest thing that could possibly work

One of the ironies of this kind of advice is that it's best for people who already have a lot of experience and have the judgement to apply it. For instance, how do you know what the "simplest thing" is? And how can you be sure that it "could possibly work"?

Yesterday I had a problem with my XLSX importer (which I wrote myself--don't ask why). It turned out that I had neglected to handle XML namespaces properly because Excel always exported files with a default namespace.

Then I got a file that added a namespace to all elements and my importer instantly broke.

For example, Excel always outputs <cell ...> whereas this file has <x:cell ...>.

The "simplest thing that could possibly work" was to remove the namespace prefix and just assume that we don't have conflicting names.

But I didn't feel right about doing that. Yes, it probably would have worked fine, but I worried that I was leaving a landmine for future me.

So instead I spent 4 hours re-writing all the parsing code to handle namespaces correctly.

Whether or not you agree with my choice here, my point is that doing "the simplest thing that could possible work" is not that easy. But it does get easier the more experience you have. Of course, by then, you probably don't need this advice.

We attempt to address this problem at work with an extra caveat to never add code "in the wrong direction" -- so it's fine (usually preferable) to have a partial implementation, as long as it's heading in the direction we'd like the more complete implementation to go in. Basically "KISS, but no hacks".