Source packages are a thing.

AUR is a repository for source packages (in Arch it’s called PKGBUILD) from users. You can write PKGBUILD yourself or just download it from AUR if someone already made it.

There is this one: https://gitlab.archlinux.org/archlinux/buildbtw/

Yeah I understand that it can install a DE into the container and stream it, but I wanted to stream my existing DE with the same configuration.

Interesting tech! But my use case was to stream my desktop 🙂