Any particular reason that you didn't want to use the Lodash debounce? https://docs-lodash.com/v4/debounce/ https://www.npmjs.com/package/lodash.debounce (mentioning it since Lodash is loaded by Observable by default, right?)

No, I just didn't know of it :)

Surprisingly common problem; if I had a nickel for every time I implemented something that Lodash then turned out to already have, with more features and a faster implementation too, I'd have three nickels.

One suggestion fil, in an observable context debounce is probably most likely used with a text input. It might be worth showing here an example of how that would work. It's not that complicated currently but the combination of the callback, bouncer, mutable, etc. can make it conceptually harder to transfer this example to the input version.

Good idea. Here's an example: https://observablehq.com/@recifs/input-debounce