Javascript engine with good interoperability with JVM and CLR

Question

Due to the huge resources behind it, Javascript seems to rapidly becoming the scripting language of choice for applications, particularly those with a web front end. I have

Answer 1

Are there any robust efforts that would allow users to call JVM/CLR libraries from Javascript

If you don't mind using TypeScript, try 1c, which also allow type checking and autocompletion for JVM libraries.