Rayon is a crate that makes it easy to write code that executes in parallel. Take a function that looks like this. It'll execute on a single thread. fn sum_of_

Rayon is a crate that makes it easy to write code that executes in parallel. Take a function that looks like this. It'll execute on a single thread. fn sum_of_squares(input: &[i32]) -> i32 { input.iter() .map(|&i| i * i) .sum() } If you changed it to input.par_iter() then it executes in parallel on multiple threads.