That depends on why you use Scala?
Do you use Scala as a better Java? If so, Nim may be what you want.
Do you use Scala for its incredible type system? Rust may be what you want.
Do you use Scala for its functional tendencies? Rust may be what you want.
As an aside, I've found that once you get over the Rust learning curve, writing 'correct' programs is easier in Rust than any other language I've used. And for data centric applications, being 'correct' is extra important.