My point is that Lua-the-language provides similar expressive power to Python-the-language (including basic stuff like lookup tables), while remaining smaller and simpler to understand than the POSIX shell. It's also simpler to vendor than Python, and you probably want to vendor this kind of stuff to avoid the pain of bootstrapping / circular dependencies.

Now I haven't built a build/packaging system like xbps or apk (few people did), but I've been in charge of devops/releng at work for a decade - and if I learned anything at all, it's that it's better to start with the simplest tool that can do the job, and slowly add what you need. E.g. I wrote a tool in 2016 to replace Ansible in my team, and all of this time it's just been doing its job: <https://github.com/rollcat/judo>. Turned out nobody actually needed the kitchen sink.