My point is, this is doable without local dependencies or configuration of any sort. The ideal solution for my team is a few extra lines in our docker compose file and that’s it. Magic sync - as a concept - satisfies this requirement, barring the fs events being lost (which is something that needs to be fixed/maybe has been fixed in osxfs).
Even building docker-sync in Go is a nonstarter in my book because it still requires something extra running on the host (though losing the Ruby dependency is nice).