I guess the clearer way to state my point is that possibility and convenience are different things.
`build.rs` scripts are Turing complete, and you can make syscalls, so you can call arbitrary other build systems. The difference in difficulty varies from language to language: C usually has few dependencies (because dependency management is fragmented and thus difficult) and so is often straightforward to compile, but other languages aren't always as easy.
With a tangled mess of FFI dependencies Cargo stops being the best tool for the job.
`build.rs` scripts are Turing complete, and you can make syscalls, so you can call arbitrary other build systems. The difference in difficulty varies from language to language: C usually has few dependencies (because dependency management is fragmented and thus difficult) and so is often straightforward to compile, but other languages aren't always as easy.
With a tangled mess of FFI dependencies Cargo stops being the best tool for the job.