"from whatever language you want" - in practice, not really. If you have a language that relies on gc or some kind of vm then you are also going to have to deli

"from whatever language you want" - in practice, not really. If you have a language that relies on gc or some kind of vm then you are also going to have to deliver all the asm.js code for the vm. That's potentially a lot of code to deliver to the browser, could you use threads efficiently in your implementation etc. There's no story yet for anything beyond a statically compiled language and even if there is a story you would probably have to wait a long time to see whether it would deliver anything in practice.