I used to take this approach when building new integrations. Then I realized (1) most documentation sucks (2) there's far too much to remember (3) much of it is conditional (4) you don't always know what matters until it matters (e.g. using different paths of implementation).
What works much better is having an intentional review step that you come back to.
Most of the time QA can tell you exactly how the product works, regardless of what the documentation says. But many of us haven’t seen a QA team in five, ten years.
You say this like trivial misstakes did not happen all the time in classical engineering as well.
If there is a memory leak, them this is a flaw, that might not matter so much for a specific product, but I can also easily see it being forgotten, if it was maybe mentioned somewhere in the documentation, but maybe not clear enough and deadlines and stress to ship are a thing there as well.
Just try harder. And if it still breaks, clearly you weren't trying hard enough!
At some point you have to admit that humans are pretty bad at some things. Keeping documentation up to date and coherent is one of those things, especially in the age of TikTok.
Better to live in the world we have and do the best you can, than to endlessly argue about how things should be but never will become.
Shouldn't grey beards, grizzled by years of practicing rigorous engineering, be passing this knowledge on to the next generation? How did they learn it when just starting out? They weren't born with it. Maybe engineering has actually improved so much that we only need to experience outages this frequently, and such feelings of nostalgia are born from never having to deal with systems having such high degrees of complexity and, realistically, 100% availability expectations on a global scale.
They may not have learned it but being thorough in general was more of a thing. These days things are far more rushed. And I say that as a relatively young engineer.
The amount of dedication and meticulous and concentrated work I know from older engineers when I started work and that I remember from my grand fathers is something I very rarely observe these days. Neither in engineering specific fields nor in general.
We were talking about making a missile (v2) with an extended range, and ensuring that the developers who work on it understand the assumption of the prior model: that it doesn't use free because it's expected to blow up before that would become an issue (a perfectly valid approach, I might add). And to ensure that this assumption still holds in the v2 extended range model. The analogy to Ariane 5 is very apt.
Now, there can be tens of thousands of similar considerations to document. And keeping up that documentation with the actual state of the world is a full time job in itself.
You can argue all you want that folks "should" do this or that, but all I've seen in my entire career is that documentation is almost universally: out of date, and not worth relying on because it's actively steering you in the wrong direction. And I actually disagree (as someone with some gray in my beard) with your premise that this is part of "rigorous engineering" as is practiced today. I wish it was, but the reality is you have to read the code, read it again, see what it does on your desk, see what it does in the wild, and still not trust it.
We "should" be nice to each other, I "should" make more money, and it "should" be sunny more often. And we "should" have well written, accurate and reliable docs, but I'm too old to be waiting around for that day to come, especially in the age of zero attention and AI generated shite.
If ownerless code doesn’t result in discoverability efforts then the whole thing goes off the rails.
I won’t remember this block of code because five other people have touched it. So I need to be able to see what has changed and what it talks to so I can quickly verify if my old assumptions still hold true
>I wonder how that information is easily found afterwards.
Military hardware is produced with engineering design practices that look nothing at all like what most of the HN crowd is used to. There is an extraordinary amount of documentation, requirements, and validation done for everything.
There is a MIL-SPEC for pop tarts which defines all parts sizes, tolerances, etc.
Unlike a lot in the software world military hardware gets DONE with design and then they just manufacture it.
For the new system to be approved, you need to document the properties of the software component that are deemed relevant. The software system uses dynamic allocation, so "what do the allocation patterns look like? are there leaks, risks of fragmentation, etc, and how do we characterise those?" is on the checklist. The new developer could try to figure this all out from scratch, but if they're copying the old system's code, they're most likely just going to copy the existing paperwork, with a cursory check to verify that their modifications haven't changed the properties.
They're going to see "oh, it leaks 3MiB per minute… and this system runs for twice as long as the old system", and then they're going to think for five seconds, copy-paste the appropriate paragraph, double the memory requirements in the new system's paperwork, and call it a day.
