I usually hear about people using Rust with C. You use Rust and C++. If you use them together, how easy is it to call Rust from C++ and vice versa? And can you

I usually hear about people using Rust with C. You use Rust and C++. If you use them together, how easy is it to call Rust from C++ and vice versa? And can you do that with their standard interfaces instead of watering it down to the lowest, common denominator?