+ - systemd-bus-proxyd needs to enforce good old XML policy
+ - port exit-on-idle logic to byebye ioctl
+ - allow updating attach flags during runtime
+ - pid1: peek into activating message when activating a service
+ - introduce sd_bus_emit_object_added()/sd_bus_emit_object_removed() that automatically includes the build-in interfaces in the list
+ - constructors for bus messages should probably not be OK with a NULL bus pointer
+ - .busname units should not use get_user_creds()/get_cgroup_creds() but instead do NSS only in temporarily forked off child