Well this is depressing, I just reimplemented the base64 URL to use LZ78 compression, but it turns out the input compresses so badly the URL only gets longer: https://observablehq.com/d/87a3330fce4e42d3

Here it is in neatly factored out cells: https://observablehq.com/d/83949b341a52c742

I'm sorry, that sounds like a great idea though! I tried https://github.com/KilledByAPixel/JSONCrush the other day but it errored on first try so I didn't have a further look... But having shorter URLs would be great for sure!

I'm now trying using muon, it should encode the numbers a bit better

Blargh, nope. Not production-ready yet :(

Sorry man, tried to help but it will take a bit more work than a quick break. Might pick it up again later though :)

Thanks for you help! In the meantime I also tried json-url, but again didn't really shorten the URL much ☹️