Embassy
Embassy is a Rust framework for building embedded applications. It leverages async/await for cooperative multitasking. It also supports multiple “executors” for true preemptive multitasking.
  nRF52 DK Embassy Tutorial    
  A step-by-step guide to building an Embassy application for the nRF52 DK. 
  nRF52 DK Embassy Tutorial 
   A step-by-step guide to building an Embassy application for the nRF52 DK. 
 In my opinion, although async/await seems like a great way to write co-operative code, it does force you to write code that only awaits on one thing at once, which is a major gotcha which makes me believe event driven state machines are a better option.