Prebuild files

[pjebs]

@ccbrown I was wondering if you have instructions on how to prebuild those object files and also how to link them all together at the end?

[ccbrown]

I haven't done this in several years, so I'm afraid all I can tell you is what's in the README: The files in ./prebuilt were produced by copying them from Go's cache after compiling anything for WASM.

I'm sure there's a much better way, and I can't guarantee what I did before would even still work, but I built something for WASM using GOOS=js GOARCH=wasm go build . and then hunted down the object files in the Go cache.