There will be an update posted on #894 soon, but this project is not actively developed at this time, so binary size isn't going to change.

More active development is happening on Go's WebAssembly support, so I recommend looking at that (also see issues golang/go#29478 and golang/go#6853). There may also be forks that will take a different approach.

sounds great. how do we wasm gopherjs? where's the repo for the transitioning of this project to wasm "type"?

See golang.org/wiki/WebAssembly.

This can been discussed in a lot of detail in #136.

In short, currently there isn't a way to significantly cut down output size without a breaking change for the existing users or incompatibility with mainline Go. This is something that we'd like to address eventually though, so feel free to subscribe to #136.