You're sort of right but it depends on the races and the data structures. If you depend on a remote function and ordering is important lots of problems can hap

You're sort of right but it depends on the races and the data structures. If you depend on a remote function and ordering is important lots of problems can happen. I've definitely needed more locking primitives and ordering but it's mostly for remote code. There are also a ton of bugs that can happen with memory allocation. For example if you do 50 async and they all come back and once and try to all allocate memory and then perform some action at the end you can have too many in flight and then use too much memory. It's not really threaded but you can run into similar problems. I've done 10+ years of core JVM threading with raw threads and softare transactional memory datastructures and CAS operations and my experience there helps a ton. Async is definitely not just 'free'