Ask HN: Most interesting tech you built for just yourself?

A website to see a map of the world's tides, and bidirectional predictions for individual stations (edit: worldwide too, forgot I added that). The UI/UX is... archaic, but that's just how I wanted it. It works fully offline. https://solunar.pages.dev

Most fun part was transcribing 70+ year old NOAA tide calculation mathematic/astronomic/hydrologic research papers into modern TypeScript. Approach is semi-documented here: https://github.com/JacksonKearl/solunar

That's just cool.

that is cool, but I'm curious when the highest tide vs lowest tide of the year is.

That is really cool!

I’ve wanted to do this with Canadian data for years! My wife works for the organization which tracks our national tide data and builds our prediction models. It’s extremely fascinating stuff.

I’m looking forward to digging into your work. I haven’t really known where to start, but I can probably get a lot of inspiration here. Nice work!

I use MouseGestures so I often get fun surprises on projects like this when I right-click and then drag my cursor to close the tab. Yours might have been the best one yet!

It will change station to station, but if you open the station details page, adjust X Range to something like 28/180 days, then tune low pass to filter out all the high frequency (daily) fluctuations, you might get your answer. Some stations don't have strong Solar contributions, and won't change much on an annual basis, you can enable the Harmonics toggle and see if any show up on the outside in yellow (disable Sun).

I did consider adding a "max finding" mode of some sort, but that's never really been my use case.

Cool! Would love to have some extra datapoints. This is what the raw data I use looks like https://tidesandcurrents.noaa.gov/harcon.html?id=9410580#

It's a very nice, UI. The "viewing port" concept is very nice. A slider for timescale in the viewing window would be great! Also would be great to see worldwide cities tides :) edit: using the x-range view is an interesting time slider - I found the options toggle

Looks nice, would love something like that for Europe.

Unfortunately while US's NOAA provides all the data needed free of charge (with an API to boot), the UK government's equivalent charges an MSRP of £38.30 and requires finding and contacting an authorized distributor, though the data does seem to be more worldwide. I haven't seen other offerings.

https://www.admiralty.co.uk/publications/publications-and-re...

If you are OK with R, there is some good code here that makes predictions from harmonics: https://dankelley.github.io/oce/reference/tidedata.html

Of course, you can download the predictions from DFO too, e.g., https://api-iwls.dfo-mpo.gc.ca/swagger-ui/index.html

Hey, thanks! I didn’t realize they have a prediction API. I assumed I’d need to produce a lot of this data myself from a giant csv or similar. This is awesome!