Building using freedesktop-sdk 1.8 as a base, instead of / as well as Debian
It would be good to have a completely BuildStream-based build pipeline. The Freedesktop SDK 1.8 project provides a distro-agnostic base, starting from a compiler bootstrap.
It currently lacks various dependencies of gnome-build-meta compared to the Debian base, we would need to work out where these should live and add them as needed.
This would be nice-to-have for #16 (closed) (building GNOME Flatpak runtimes from gnome-build-meta)