This code block doesn't actually work the way the Kotlin one does. Async functions are mere pull-based state machines, so both `one` and `two` will compute serially, without concurrency.

What you need is:

    use futures::join;

    let result = executor::block_on({
        let one = async { do_something_useful_one() };
        let two = async { do_something_useful_two() };
        let (one, two) = join!(one, two);
        one + two
    }); 

I feel like this might be a common stumbling block and hope there will be a Clippy check for this or something.