I've used everything from pthreads to goroutines to Those Things That Ruby 1.8 Calls Threads Even Though They're Not Really. It's not that multithreaded code is

I've used everything from pthreads to goroutines to Those Things That Ruby 1.8 Calls Threads Even Though They're Not Really. It's not that multithreaded code is inherently hard, it's just that it increases the number of interactions you have to think about exponentially. If you're used to thinking of programs as a procedural set of state manipulations, you will be incapable of reasoning about a multiprocessing system because between every two steps in your algorithm there can be an arbitrary number of steps from other algorithms which will wreak havoc with your state.