With a quick search I can see that the `in-dexter` package [1] provides something quite similar, though I'm not sure if it covers all usecases.
If you want to handroll this yourself you can probably have your `index` emit some `metadata` [2] which you can then `query` [3] for in your `printindex`. All of this would work inside the typst compiler and there would be no need for running an external `makeindex` command.
Thanks. My search found that also, but it didn't appear to have the features I need, at least not at the time. If LaTeX becomes vexing enough, I'll consider the custom workflow you're describing. Thanks for the tips.
https://en.wikibooks.org/wiki/LaTeX/Indexing