I've written a website that archives all my posts/tweets/toots/skeets across different microblogging platforms!
It's fun to be able to see similar posts that I wrote at completely different times. It also lets me edit links that have bitrotted.
I've been working on a search tool for a website with 9K items and a dumb implementation works just fine. I'd normally gravitate to a library or tool like elasticsearch (ES).
Adding custom filters etc is trivial on handrolled code. I wonder what scale requires actual search infra like ES.