You could use the following to get the path to your assets.

    import (
        "go/build"
        "path/filepath"
    )
    
    pkgInfo, err := build.Import("github.com/minikomi/pipesock", "", 0)
    if err != nil {
        panic(err)
    }
    webDirPath := filepath.Join(pkgInfo.Dir, "default")