Great work! But is there any reason that you didn't build on top of the really nice V8 binding https://github.com/ry/v8worker instead of Duktape?
With go-duktape, you can compile CandyJS just lake a normal Go package without any other tool or library.
Other reason is that many of the features are based on ECMA6 Proxy, something that is not supported on v8.