It's a library, so only half an answer to your question, but there's a fantastic library called rayon[1] created by one of the core contributors the the Rust language itself, Niko Matsakis. It lets you use Rust's iterator API to do extremely easy parallelism:

  list.iter().map(<some_fn>)

becomes:

  list.par_iter().map(<some_fn>)

Seeing as in the original example code, the final copies into the minifb have to be sequential due to the lock anyway, all the usage of synchronization primitives and in fact the whole loop could be replaced with something like:

  let rendered = buffers.par_iter().map(<rendering>).collect();  
  for buffer in rendered.iter() {  
    // The copy from the article  
  }

I've not written much Rust in a while, so maybe the state of the art is different now, but there are a lot of ways to avoid having to reach specifically for synchronization primitives.