How to specify cxx_binary runtime dependencies?

I'm building a cxx_binary that has some runtime dependencies, both in the form of plugin shared libraries (plugin because they are loaded at runtime using dlopen and should not participate in the build) and configuration files. How do I specify this in Buck2?

It seems like cxx_binary's resources is supposed to be used for that but when I use it I only get a resources.json file in the buck-out folder and they are not in the working directory of the binary when I call buck2 run.

Has it simply not been implemented yet? Is the file supposed to be read by an external tool?

Thanks for making Buck2!