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> I once interviewed a candidate[1] who had printed off a whole list like this and insisted on grinding through the whole thing. It was weirdly offputting, but

> I once interviewed a candidate[1] who had printed off a whole list like this and insisted on grinding through the whole thing. It was weirdly offputting, but he was such a monster programmer that he was already a clear hire. It gave an insight into the thoroughness of his nature though and showed that he was absolutely perfect for the (critical) role we were hiring him for where mistakes were extremely costly. Would you share some more information on what kind of role it was? And what kind of qualities would you look for when hiring someone for that kind of position? I aspire to work in such role (where pedantry is appreciated, instead of tolerated) one day, and I'd be grateful for any such information or hints.

Cthulhu_ 4y ago
I mean I'm reading that and I just wonder if the grandparent only hired one person for that role; if it's that critical, you should never rely on one person. You need a team and thorough QA. It does remind me of this article I once read about how things happened at NASA, with every line of code extensively documented and discussed, and teams competing with each other to find bugs.
badpun 4y ago
Linux kernel programming is probably like this. There are no automatic tests, so the more pedantic you are, the less bugs you'll introduce.
- silvestrov 4y ago
  accounting is another job where mistakes can be very costly monetary, customer relationship or law. Until you have worked with (internationonal) accounting, you don't realize how complex it can be.
- arwhatever 4y ago
  The fewer bugs you’ll introduce. I don’t know squat about kernel programming, though. :-)
  - danielheath 4y ago
    You are also likely introducing bugs which are lesser :p
  - dahart 4y ago
    Time to unlearn some things about English that aren’t true. Less is fine to use. Also, myriad can be a noun, literally has always been used figuratively, responding to ‘how are you?’ with ‘I’m good’ is perfectly fine. I’ve tried correcting people too, but the older I get, the more I find out that it’s me who’s wrong and policing language is almost never correct. The idea to use “fewer” for countable things was someone’s personal preference. https://www.merriam-webster.com/words-at-play/fewer-vs-less https://www.merriam-webster.com/words-at-play/fewer-vs-less “This rule is simple enough and looks easy enough to follow, but it's not accurate for all usage. The fact is that less is also sometimes used to refer to number among things that are counted. “This isn't an example of how modern English is going to the dogs. Less has been used this way for well over a thousand years—nearly as long as there's been a written English language.” See also the list of common counter examples.
    - jamessb 4y ago
      arwhatever made a specific comment about the use of "less mistakes" vs "fewer mistakes", not a broader claim about the use of fewer/less for countable/uncountable amounts. I think the relevant part of the "Exceptions to the Rule" section on that page is: > The use of less to modify ordinary plural count nouns (as in "made less mistakes") is pretty rare in writing and is usually better avoided, though it does occur frequently in speech. The exceptions (refering to distances/sums of money/units of time and weight/ statistical enumerations, phrases like "or less", and uses of "less" immediately following a number) aren't relevant here. But both are "fine" in that they will be correctly understood.
      - dahart 4y ago
        I don’t follow your distinction about broad vs specific. The specific correction was offered based solely and entirely on the general rule of thumb, no? What other line do you see here? > both are “fine” in that they will be correctly understood. Agree! So much! I would go further, because I think this is the most important point: there is not a way to misunderstand the use of “less” in this context, which means that correcting people is purely pedantic, and not a functional issue or helping avoid potential misunderstanding. Not only that, but sometimes people use “less” rather than “fewer” intentionally for countable things than can have a qualitative weight to them, as @danielheath pointed out. If the parent was trying to say that the bugs themselves could be both fewer in number, and also less damaging in scope, then less and fewer have two different meanings, and less is the more correct word to use. > use of less […] is pretty rare in writing and is usually better avoided Yes, I chose to emphasize that the rule is not absolute. Lots of people claim the rule is absolute, and a correction implies that point of view. My point is that even if using ‘less’ is better avoided, unsolicited corrections in public are also better avoided, because the rule is not absolute and in this case cannot be mistaken or misunderstood. Worth noting that HN comments are not formal writing, and social media by and large is closer to informal speech, so the snippet you quoted can be viewed as validating use of less in this specific case.
- rpastuszak 4y ago
  > There are no automatic tests #til and also #wtf In all seriousness, can you recommend any resources on why is that the case and how kernel is tested?
  - bruce343434 4y ago
    I can't speak about the kernel but personally I prefer proofs of correctness over testing.
    - zasdffaa 4y ago
      If you haven't any experience of doing proofs of correctness, it may be worth getting some before being certain about what you prefer. Proofs are hard. Proofs of something like the kernel... dream on.
    - zelphirkalt 4y ago
      Those are very hard to achieve though for some non-trivial C code.
  - gjulianm 4y ago
    There are tests: https://www.kernel.org/doc/html/latest/dev-tools/testing-overview.html https://www.kernel.org/doc/html/latest/dev-tools/testing-ove... However, the kernel is fairly hard to test because it's the kernel: - A lot of code paths are fully dependent on hardware that can't be mocked. How would you test the bootloader, for example? Or code that depends on a certain processor architecture? The only way is to actually run the code on that hardware. - Similarly, it's hard to test the drivers. A lot of them are made by vendors, and the only way to test is against the devices themselves. Even if you could emulate the device and connect that to the driver, there's a lot of things that you won't cover (the communication path, the device misbehaving...) - It's hard to test things that the runtime depends on. For example, if you try and test the memory subsystem, how do you manage the memory to actually run the tests? Kernel testing is hard for the same reasons kernel development alone is hard, you're building the thing that all other tools require to run.
    - 4y ago
- winReInstall 4y ago
  The tests were the friends we made along the way, and inside all of us all along >D
- nyanpasu64 4y ago
  For the longest time I viewed kernel programming as an exalted realm of "optimized bare-metal software written by visionaries and wizards" (like operating system core developers of the Dave Cutler variety). Having had the misfortune of dabbling in reverse-engineering Windows drivers and debugging in-tree Linux kernel drivers, I now believe they're often messy hackjobs written by low-paid average-skilled embedded developers, no less fallible than the average enterprise Java programmer (https://blog.ffwll.ch/2022/08/locking-hierarchy.html https://blog.ffwll.ch/2022/08/locking-hierarchy.html expresses a similar sentiment). And I feel the maintainers are sometimes spread far too thin (Dmitry Torokhov manages a good chunk of Linux's entire input system, no wonder he lets mistakes slip by in the touchpad driver, I'm just disappointed I reported a bug to the mailing lists and never got a reply after like a month). EDIT: The wizards are out there, for example https://pvk.ca/Blog/2019/01/09/preemption-is-gc-for-memory-reordering/ https://pvk.ca/Blog/2019/01/09/preemption-is-gc-for-memory-r..., but they're not evenly distributed, and perhaps the insane cutting-edge code they write (and the less insane code I write) isn't necessarily dependable, since by definition they lie on the edge of human understanding.
  - yencabulator 4y ago
    Drivers are the worst parts of Linux, the realm of drive-by contributions. Go read e.g. VFS or networking/TCP internals.
- deleted 4y ago
  [deleted]
seanhunter 4y ago
He was looking after and developing a key set of extremely sensitive servers (custom key/value stores that served all the global risk and pricing infrastructure for a major investment bank). The desirable qualities (besides being a very good programmer) for such a role include: 1)Being very calm and having exceptional judgement in a crisis. Crises happen a lot. 2)Being sufficiently frightened of breaking things that you proceed with caution 3)Being good enough and having enough confidence in your abilities that you actually manage to get things done in spite of the very significant consequences of mistakes.

Cthulhu_ 4y ago

I mean I'm reading that and I just wonder if the grandparent only hired one person for that role; if it's that critical, you should never rely on one person. You need a team and thorough QA. It does remind me of this article I once read about how things happened at NASA, with every line of code extensively documented and discussed, and teams competing with each other to find bugs.

badpun 4y ago

Linux kernel programming is probably like this. There are no automatic tests, so the more pedantic you are, the less bugs you'll introduce.

silvestrov 4y ago
accounting is another job where mistakes can be very costly monetary, customer relationship or law. Until you have worked with (internationonal) accounting, you don't realize how complex it can be.
arwhatever 4y ago
The fewer bugs you’ll introduce. I don’t know squat about kernel programming, though. :-)
- danielheath 4y ago
  You are also likely introducing bugs which are lesser :p
- dahart 4y ago
  Time to unlearn some things about English that aren’t true. Less is fine to use. Also, myriad can be a noun, literally has always been used figuratively, responding to ‘how are you?’ with ‘I’m good’ is perfectly fine. I’ve tried correcting people too, but the older I get, the more I find out that it’s me who’s wrong and policing language is almost never correct. The idea to use “fewer” for countable things was someone’s personal preference. https://www.merriam-webster.com/words-at-play/fewer-vs-less https://www.merriam-webster.com/words-at-play/fewer-vs-less “This rule is simple enough and looks easy enough to follow, but it's not accurate for all usage. The fact is that less is also sometimes used to refer to number among things that are counted. “This isn't an example of how modern English is going to the dogs. Less has been used this way for well over a thousand years—nearly as long as there's been a written English language.” See also the list of common counter examples.
  - jamessb 4y ago
    arwhatever made a specific comment about the use of "less mistakes" vs "fewer mistakes", not a broader claim about the use of fewer/less for countable/uncountable amounts. I think the relevant part of the "Exceptions to the Rule" section on that page is: > The use of less to modify ordinary plural count nouns (as in "made less mistakes") is pretty rare in writing and is usually better avoided, though it does occur frequently in speech. The exceptions (refering to distances/sums of money/units of time and weight/ statistical enumerations, phrases like "or less", and uses of "less" immediately following a number) aren't relevant here. But both are "fine" in that they will be correctly understood.
    - dahart 4y ago
      I don’t follow your distinction about broad vs specific. The specific correction was offered based solely and entirely on the general rule of thumb, no? What other line do you see here? > both are “fine” in that they will be correctly understood. Agree! So much! I would go further, because I think this is the most important point: there is not a way to misunderstand the use of “less” in this context, which means that correcting people is purely pedantic, and not a functional issue or helping avoid potential misunderstanding. Not only that, but sometimes people use “less” rather than “fewer” intentionally for countable things than can have a qualitative weight to them, as @danielheath pointed out. If the parent was trying to say that the bugs themselves could be both fewer in number, and also less damaging in scope, then less and fewer have two different meanings, and less is the more correct word to use. > use of less […] is pretty rare in writing and is usually better avoided Yes, I chose to emphasize that the rule is not absolute. Lots of people claim the rule is absolute, and a correction implies that point of view. My point is that even if using ‘less’ is better avoided, unsolicited corrections in public are also better avoided, because the rule is not absolute and in this case cannot be mistaken or misunderstood. Worth noting that HN comments are not formal writing, and social media by and large is closer to informal speech, so the snippet you quoted can be viewed as validating use of less in this specific case.
rpastuszak 4y ago
> There are no automatic tests #til and also #wtf In all seriousness, can you recommend any resources on why is that the case and how kernel is tested?
- bruce343434 4y ago
  I can't speak about the kernel but personally I prefer proofs of correctness over testing.
  - zasdffaa 4y ago
    If you haven't any experience of doing proofs of correctness, it may be worth getting some before being certain about what you prefer. Proofs are hard. Proofs of something like the kernel... dream on.
  - zelphirkalt 4y ago
    Those are very hard to achieve though for some non-trivial C code.
- gjulianm 4y ago
  There are tests: https://www.kernel.org/doc/html/latest/dev-tools/testing-overview.html https://www.kernel.org/doc/html/latest/dev-tools/testing-ove... However, the kernel is fairly hard to test because it's the kernel: - A lot of code paths are fully dependent on hardware that can't be mocked. How would you test the bootloader, for example? Or code that depends on a certain processor architecture? The only way is to actually run the code on that hardware. - Similarly, it's hard to test the drivers. A lot of them are made by vendors, and the only way to test is against the devices themselves. Even if you could emulate the device and connect that to the driver, there's a lot of things that you won't cover (the communication path, the device misbehaving...) - It's hard to test things that the runtime depends on. For example, if you try and test the memory subsystem, how do you manage the memory to actually run the tests? Kernel testing is hard for the same reasons kernel development alone is hard, you're building the thing that all other tools require to run.
  - 4y ago
winReInstall 4y ago
The tests were the friends we made along the way, and inside all of us all along >D
nyanpasu64 4y ago
For the longest time I viewed kernel programming as an exalted realm of "optimized bare-metal software written by visionaries and wizards" (like operating system core developers of the Dave Cutler variety). Having had the misfortune of dabbling in reverse-engineering Windows drivers and debugging in-tree Linux kernel drivers, I now believe they're often messy hackjobs written by low-paid average-skilled embedded developers, no less fallible than the average enterprise Java programmer (https://blog.ffwll.ch/2022/08/locking-hierarchy.html https://blog.ffwll.ch/2022/08/locking-hierarchy.html expresses a similar sentiment). And I feel the maintainers are sometimes spread far too thin (Dmitry Torokhov manages a good chunk of Linux's entire input system, no wonder he lets mistakes slip by in the touchpad driver, I'm just disappointed I reported a bug to the mailing lists and never got a reply after like a month). EDIT: The wizards are out there, for example https://pvk.ca/Blog/2019/01/09/preemption-is-gc-for-memory-reordering/ https://pvk.ca/Blog/2019/01/09/preemption-is-gc-for-memory-r..., but they're not evenly distributed, and perhaps the insane cutting-edge code they write (and the less insane code I write) isn't necessarily dependable, since by definition they lie on the edge of human understanding.
- yencabulator 4y ago
  Drivers are the worst parts of Linux, the realm of drive-by contributions. Go read e.g. VFS or networking/TCP internals.
deleted 4y ago
[deleted]

seanhunter 4y ago

He was looking after and developing a key set of extremely sensitive servers (custom key/value stores that served all the global risk and pricing infrastructure for a major investment bank). The desirable qualities (besides being a very good programmer) for such a role include: 1)Being very calm and having exceptional judgement in a crisis. Crises happen a lot. 2)Being sufficiently frightened of breaking things that you proceed with caution 3)Being good enough and having enough confidence in your abilities that you actually manage to get things done in spite of the very significant consequences of mistakes.