IMO it's actually incredibly well-documented and thoughtfully organized for a one-person project! You should be proud of what you've put together here!
It's a Debian server running nginx into a bunch of custom java services that use the spark microframework[1]. I use a MariaDB server for link data, and I've built a bespoke index in Java.
[1] https://sparkjava.com/ I don't use springboot or anything like that, besides Spark I'm not using frameworks.
Do you happen to have a writeup somewhere of your tech stack?