Ask HN: What is the most impactful thing you've built?

I made a Chrome extension used by 17 people (including me). It adds fuzzy search to the main Old Javanese->English dictionary website. I assume these users are all scholars of some sort. It’s unlikely to be the biggest impact of what I’ve done in terms of numbers, but I hope it may help unlock insights in this under-resourced language.

For me, it was the second application I ever released, when I was a student at university and still didn't really know how to program properly.

The application was Dash Board[1] for Newton OS, and it only ran on the final generation of Newton hardware (created by Apple, but spun out as a separate company in its final days, before being killed by Steve Jobs shortly after his return).

It "only" sold a few thousand copies. (But it was during the warez heyday, and I am pretty sure there were also tens of thousands of bootleg copies being used, thanks to the registration code generator by "DocNZ" that was widely shared on Hotline back then.)

But that was really pretty great, since the final MP2000/2100 generation of hardware it required was thought to have only sold about 200,000 devices in total.

I have since had a fairly normal software engineer career, and have worked on apps that shipped far more copies, and today I work on customer facing web applications and API SDKs that have more users, and arguably do stuff that is more "important" (e.g. help companies manage large fleets of machines/robots/IoT stuff) than what Dash Board did — which was basically just improve the user interface of the Newton.

But it's 100% clear to me that the magnitude of user impact of Dash Board was much higher than any other thing I've built. People really loved it — I know because hundreds of them actually wrote to us to let us know. (LOL I mean wrote to me "me" — old habits of pretending the company wasn't just one student in his tiny apartment die hard).

Of course, I made more money later, and worked on things that touched a much larger number of people's lives. But "impact" has both X and Y axes. It was the depth of the users' fondness for Dash Board that makes it eclipse everything since. I don't think there are that many chances to just go for "user delight" as the number one metric.

For me, developer satisfaction is a function of that user delight more than anything else.

[1]: http://www.fivespeedsoftware.com/dashboard

[2]: 15 years later, I open-sourced the code and gave it a proper retrospective: https://github.com/masonmark/Dash-Board-for-Newton-OS

Can you elaborate a little bit more about how you partitioned it?

flexboxpatterns.com — I don’t have a way to measure its actual impact on folks, but it’s still kicking around and getting traffic after 7 years.

I've developed an application that presents information about a patient's circulatory system to anaesthetists during surgery to give them clearer information about the patients heart and vasculature so that they can make finer grained, individualised treatment decisions. There's currently only a small group of users, as we haven't been able to afford to go through clinical trials yet, but the evidence is mounting that it is getting patients through surgery with fewer complications and better prospects of a full fast recovery. I've been in the theatre and watched someone wake up after a 9 hour surgery and instantly be alert enough to say they'd like a cup of tea, which the anaesthetist attributed to the decisions he was able to make informed by the software. It seems as if it has already had an significant positive impact on the health of the people treated by anaesthetists using the software. If further studies support the anecdotal evidence from our users, the software might have a significant impact on millions of people.