Hey, Oso engineer here. Good question. The rust core is indeed called from the ruby library (as it is with all of our 5 other host libraries). The core itself

Hey, Oso engineer here. Good question. The rust core is indeed called from the ruby library (as it is with all of our 5 other host libraries). The core itself is pretty complex (there's a whole parser/interpreter in there), so maintaining it in a bunch of languages would be a bit hectic. There are some files inside `lib/oso/polar/ffi` that define the C bindings used by the rest of the library. Here's an example: https://github.com/osohq/oso/blob/main/languages/ruby/lib/oso/polar/ffi/query.rb https://github.com/osohq/oso/blob/main/languages/ruby/lib/os... We use the ffi gem to make that work: https://github.com/ffi/ffi https://github.com/ffi/ffi EDIT: hobofan beat me to it! :)