I on the other hand think JS does need threads, but they should, to a certain extent, be automatically managed by the event loop and transparent to the programm

I on the other hand think JS does need threads, but they should, to a certain extent, be automatically managed by the event loop and transparent to the programmer. That way you get more bandwidth (workers in fact) to process your internal JS event queue. Threads are great also when you need to do CPU intensive calculations such as processing an audio file or number crunching. That's what NapaJS seems to be geared towards in fact.