It will be officially maintained by ReviversMC. The api is written in Kotlin, and is best used with Kotlin. Regardless, it should still remain functional on Java.
Get it on Jitpack!
KDocs can be found at https://reviversmc.github.io/the-mod-index-api/.
If you have a community maintained version of the api in some other language, do let us know, and we'd be happy to feature it.