Julia Packages Peacefully Coexisting in Multi-language Github Projects

I have a project that should include packages for several different languages (back end code), along with some common artifacts (front end things HTML, JS, and CSS).

Is there a way to handle this in Julia? Ideally I’d like a directory structure like this:

    |-- html/ (artifacts used by packages in various languages)
    |-- julia/ (julia code in here, along with Project.toml, Manifest.toml, and Artifacts.toml)
    +-- (directories for other languages)

I don’t see way to put a git-tree reference to html/ in the current package (wherever it happens to be hosted) into Artifacts.toml . Do you have to hard-code the repository URL to do this?

It seems like this even if there was a way to refer to a git-tree in the current package, we still have to wait for PackageSpec to allow subdirectories and for Registrator.jl to handle subdirectories.