It's a script that reads openzim files, and then cleans up the MediaWiki HTML into a sqlite database. The encyclopeida service then does some basic rendering to produce this website. Search and navigation is provided by tortured misuse of a PATRICIA Trie.

It's very much a one-off sort of a thing that's not super well documented, but here are the sources: https://github.com/MarginaliaSearch/encyclopedia.marginalia....

It's a surprisingly light service. I used to host it on a raspberry pi 4 for a long while, and it wasn't significantly slower than it is today.

From the footer:

>The wikipedia contents are from OpenZIM dumps, which typically lag behind the main Wikipedia project by up to a year.

That being said, while it wouldn't be a good fit for that project, Wikipedia, et al., have a fairly robust API: <https://www.mediawiki.org/wiki/API>

> The wikipedia contents are from OpenZIM dumps, which typically lag behind the main Wikipedia project by up to a year.

(edit: too late)