I would love for BonsaiDb to be able to be used from other languages. I don't think it would be terribly difficult to do. The next release adds almost all of the APIs that would be needed to build a shared library version of BonsaiDb.
Unfortunately, there are so many features I want to add, and only so many hours in each day. I'm a very happy Rustacean which means that I'm unlikely to focus on exposing BonsaiDb to other languages anytime soon.
That being said, I will do everything I can to help contributors who want to bring BonsaiDb to another language.