38 votes

Insulin pump software drops leading decimal points

27 comments

  1. [9]
    teaearlgraycold
    Link
    Remember this when someone tells you software engineers aren’t real engineers because you don’t have lives on the line.

    Remember this when someone tells you software engineers aren’t real engineers because you don’t have lives on the line.

    32 votes
    1. fraughtGYRE
      Link Parent
      Shades of the Therac-25...

      Shades of the Therac-25...

      17 votes
    2. [3]
      sparksbet
      Link Parent
      Software bugs killing people isn't even a new development... THERAC-25 should be mandatory education for anyone who even thinks about programming in a medical context. Maybe any context.

      Software bugs killing people isn't even a new development... THERAC-25 should be mandatory education for anyone who even thinks about programming in a medical context. Maybe any context.

      17 votes
      1. [2]
        redwall_hp
        Link Parent
        The THERAC-25 paper was actually required reading in senior year for my CS program's curriculum. I've said as much before on Tildes, but I'm generally in favor of software engineering requiring...

        The THERAC-25 paper was actually required reading in senior year for my CS program's curriculum.

        I've said as much before on Tildes, but I'm generally in favor of software engineering requiring some level of professional licensure (outside of a genuine hobby context). It's a field that stands to cause as much harm as medicine, law or civil engineering, and there is currently nowhere near the amount of concern for ethics in the industrial realm (more in academia).

        18 votes
    3. [4]
      lou
      Link Parent
      People really say that? Don't they know there's a lot of software in healthcare?

      People really say that? Don't they know there's a lot of software in healthcare?

      2 votes
      1. [3]
        fraughtGYRE
        (edited )
        Link Parent
        Many places allow the use of "software engineer" as a job title or for advertising open positions without accreditation from the appropriate professional engineering associations. IIRC, some...

        Many places allow the use of "software engineer" as a job title or for advertising open positions without accreditation from the appropriate professional engineering associations. IIRC, some locales go even further and allow use of the title without completion of an engineering degree.

        4 votes
        1. [2]
          nukeman
          Link Parent
          I would say most if not all of the United States allows “software engineer” to be used without an engineering degree or professional licensure. But that isn’t unique among traditional branches of...

          I would say most if not all of the United States allows “software engineer” to be used without an engineering degree or professional licensure. But that isn’t unique among traditional branches of engineering; I’m a chemical engineer (with a title of “Engineer”) and have a B.S. in Chemical Engineering, but didn’t take the PE exam. One of my coworkers has a physics degree, with an “Associate Engineer” title. The folks I’ve heard of going for a PE have been civil engineers who are working on structures where state law requires licensure for sign-off.

          12 votes
          1. [2]
            Comment deleted by author
            Link Parent
            1. stu2b50
              Link Parent
              I would add that US employers (which have extensive employment in Canada and really dominate high paying CS positions) have eroded it to the point where for the most part in Canada people just...

              I would add that US employers (which have extensive employment in Canada and really dominate high paying CS positions) have eroded it to the point where for the most part in Canada people just call themselves Software Engineers whether licensed by PE or not.

              2 votes
  2. [3]
    DanBC
    Link
    This is a link to a thread of posts. It's not a link to a single post. Please do read all of the thread. Here's the text of the first post: "Notified today that my insulin pump controller has a...

    This is a link to a thread of posts. It's not a link to a single post. Please do read all of the thread.

    Here's the text of the first post:

    "Notified today that my insulin pump controller has a bug where the leading decimal point will be dropped, ie: changing a dose of .21 units to 21 units. I can reproduce randomly ~1 in 5 times so probably a race condition. Easily one of the worst software bugs I have ever heard of."

    18 votes
    1. [2]
      Sodliddesu
      Link Parent
      Can't do that without a Twitter account. Hopefully someone will write an article soon with some sources, got a few diabetics in my life who might need to see this.

      Please do read all of the thread.

      Can't do that without a Twitter account. Hopefully someone will write an article soon with some sources, got a few diabetics in my life who might need to see this.

      22 votes
      1. CannibalisticApple
        Link Parent
        Here's a link that works without an account. Also pasting text of the second tweet, which mentions the affected device:

        Here's a link that works without an account. Also pasting text of the second tweet, which mentions the affected device:

        The device is the insulet omnipod 5 android app (the only mobile app available besides a dedicated controller - iOS is slated to release in 2024)

        17 votes
  3. [3]
    ButteredToast
    Link
    I wonder what the chain of events is that leads to the decimal only getting cut sometimes. Maybe a code path that only runs under specific conditions that treats a float as an int somewhere? I’ve...

    I wonder what the chain of events is that leads to the decimal only getting cut sometimes. Maybe a code path that only runs under specific conditions that treats a float as an int somewhere?

    I’ve not done work on such things myself but I’ve heard/read that it’s not uncommon to build critical systems to work exclusively with whole numbers to prevent drift over time as a result of float imprecision. Wonder why that wasn’t done here.

    9 votes
    1. [2]
      Comment deleted by author
      Link Parent
      1. sparksbet
        Link Parent
        Yeah now that you've mentioned it, I've encountered this same bug in my budget app -- the main difference ofc being that thr consequences are much less dangerous!

        Yeah now that you've mentioned it, I've encountered this same bug in my budget app -- the main difference ofc being that thr consequences are much less dangerous!

        4 votes
    2. sparksbet
      Link Parent
      Maybe that was done here and something fucked up with conversion. Hard to say without seeing the code. If they need to use fractions of units (which is part of the medical application, so they...

      I’ve not done work on such things myself but I’ve heard/read that it’s not uncommon to build critical systems to work exclusively with whole numbers to prevent drift over time as a result of float imprecision. Wonder why that wasn’t done here.

      Maybe that was done here and something fucked up with conversion. Hard to say without seeing the code. If they need to use fractions of units (which is part of the medical application, so they do), whether they treat them as ints or floats underlyingly there's still a risk of bugs creeping in like this if you're not vigilant.

      3 votes
  4. [2]
    yonkeltron
    Link
    I am surprised no one has mentioned OpenAPS at all.

    I am surprised no one has mentioned OpenAPS at all.

    5 votes
    1. Mendanbar
      Link Parent
      I thought about it but didn't want to sound preachy or pompous. I was quietly very glad though that I avoided all this by virtue of using open source software.

      I thought about it but didn't want to sound preachy or pompous. I was quietly very glad though that I avoided all this by virtue of using open source software.

      4 votes
  5. [10]
    Promonk
    Link
    Sincere question: why the hell does anyone sane still use Twitter? It was mostly tedious even before it was bought by a fascist megalomaniac.

    Sincere question: why the hell does anyone sane still use Twitter? It was mostly tedious even before it was bought by a fascist megalomaniac.

    24 votes
    1. [7]
      DeaconBlue
      Link Parent
      The real answer is that there isn't a good alternative that can get your news out to non-technical people. Mastodon is too complicated for my parents to figure out in 3 minutes, so they aren't...

      The real answer is that there isn't a good alternative that can get your news out to non-technical people.

      Mastodon is too complicated for my parents to figure out in 3 minutes, so they aren't going to. Twitter is not.

      11 votes
      1. [6]
        unkz
        Link Parent
        Bluesky is as simple as Twitter. The problem, as with all other alternatives, is it is an empty wasteland.

        Bluesky is as simple as Twitter. The problem, as with all other alternatives, is it is an empty wasteland.

        7 votes
        1. [4]
          CannibalisticApple
          Link Parent
          Bluesky is also invite-only, and last I checked I can't even view accounts without one of my own. Just tried looking at one a friend made for his business, took me to a log-in page. So it's not...

          Bluesky is also invite-only, and last I checked I can't even view accounts without one of my own. Just tried looking at one a friend made for his business, took me to a log-in page. So it's not good for getting information out to the masses.

          10 votes
          1. [3]
            DefinitelyNotAFae
            Link Parent
            Would you like an invite?

            Would you like an invite?

            1 vote
            1. [2]
              CannibalisticApple
              Link Parent
              Thank you for the offer, but I'm not much of a social media user. I'm on the waiting list and content to wait months, so you should save it for people who do want one!

              Thank you for the offer, but I'm not much of a social media user. I'm on the waiting list and content to wait months, so you should save it for people who do want one!

              2 votes
              1. DefinitelyNotAFae
                Link Parent
                I have five invite codes, so you're not putting me out. Let me know if you change your mind!

                I have five invite codes, so you're not putting me out. Let me know if you change your mind!

                5 votes
        2. Minori
          Link Parent
          It's still invite-only isn't it? That really slows down growth for better and worse.

          It's still invite-only isn't it? That really slows down growth for better and worse.

          5 votes
    2. [2]
      stu2b50
      Link Parent
      For the same reason I was on it before: to talk to people and communities I want to talk to. Musk has made the user experience worse, but ultimately it is what it is.

      For the same reason I was on it before: to talk to people and communities I want to talk to. Musk has made the user experience worse, but ultimately it is what it is.

      11 votes
      1. redwall_hp
        Link Parent
        Yep. I hate Musk and what he's done to it, but that's not enough for most people to leave the networks they've built. (The literal Network Effect.) And the negative sentiment, as much as it's all...

        Yep. I hate Musk and what he's done to it, but that's not enough for most people to leave the networks they've built. (The literal Network Effect.)

        And the negative sentiment, as much as it's all over English discourse, does not penetrate international communities nearly as much. I follow a lot of Japanese accounts, companies and individuals, and they're less aware of what's going on. The "X" rebrand caused more confusion than anything else, because it was immediately noticeable. But Twitter is still the most active place for news about Japanese music, animation, games, etc..

        5 votes