Shout-out to Pagefind static search
The website's search feature is implemented by a very clever and well-engineered library called Pagefind. It is many of my favorite things: fast, small, and free of dependencies I need to worry about.
The one thing that its built-in user interface couldn't do, but in a miracle of GitHub responsiveness, Liam Bigelow responded to my feature request within an hour and shipped the feature inside a week.
Tip of the hat to Liam and his colleagues at cloudcannon. If you have a static site, I strongly encourage you to check out Pagefind for your search feature. It's free, but even if it weren't, I still prefer it to all of its paid competition.