Authoring Books and Technical Documents with R MarkdownProject mention: Books.jl: Create Books with Julia | news.ycombinator.com | 2021-11-01
If you can pre-build the index, Lunr seems to work well, but it doesn't support Chinese. R/bookdown switched for these reasons recently to fuse.js.
There is discussion of some of the other options and their tradeoffs here:
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