> I use grep on a flat file, and testing now it takes 200ms for a query across my 180k history entries
200ms is order of magnitude more than I'd prefer for interactive use
I was going to say that it was "instant", because that's how it feels when using it, but got 200ms from running "time" on grepping it to include a number in the post.
Have you tried out using ripgrep [0] or fzf [1]? 200ms is quite a lot for history search, I'd expect search to be 20ms or less. In fact, it should be instantaneous as it should all fit in memory really. I've been using fzf and the searches are all faster than my monitor can display frames (so less than 16ms), although I only have 10k entries on my history as I clear it up once in a while.