There's been nothing new on the BUS1 front this year for capability-based IPC within the Linux kernel... In fact, the BUS1 out-of-tree kernel module has gone untouched for years now. But out of the BUS1 project has been Dbus-Broker for a high performance D-Bus message broker in user-space that doesn't break existing D-Bus compatibility. Out today is the newest version of that project closely tied to systemd developers.

David Rheinsberg has released Dbus-Broker 34 as the newest version of this message broker. Dbus-Broker 34 now checks for the SELinux enforcing-mode and honors its value, supports the new "ProcessFD" key in GetConnectionCredentials(), loading files from a directory will not enumerate the files in a predictable order but rather the pseudo-random order returned by the kernel, and various other changes and fixes.

Downloads and more details on the Dbus-Broker 34 release via the bus1/dbus-broker GitHub repository .