If I had to wager a guess, getting to skip parsing at runtime, better typings known to the compiler, and having a lighter runtime all help. Having good type in

If I had to wager a guess, getting to skip parsing at runtime, better typings known to the compiler, and having a lighter runtime all help. Having good type info is especially powerful for compiler optimizations, and a situation that JS get a lot less often than Java. I'm assuming the JVM is lighter overall than Node, but that's just a guess, and AOT(ish) probably helps as well.