As far as I can see, let bindings are unavailable in #js-literals within go-blocks, ie:
(go (let (link: a 1) (js/console.log #js(link: a))))
prints (link: undefined )
instead of (link: 1)
It happens both with #js(link: ..)
and #js{..}
To make it easier to reproduce the bug, I've created a minimal repository github.com/rasmuserik/cljs-bug with project.clj etc.