Yes, but not like CageFS, at least as I understand CageFS. We’re working on namespace-based containerization of users (using bubblewrap: GitHub - containers/bubblewrap: Low-level unprivileged sandboxing tool used by Flatpak and similar projects · GitHub). Transparent to users, battle-tested by major projects, very lightweight (basically instant and near-zero overhead, as it’s based around kernel features that are always active), and probably none of the risks of chroot-based options.