OpenSUSE 15.1 / Systemd 234:

Support for dynamically creating users for the lifetime of a service has been added. If DynamicUser=yes is specified, user and group IDs will be allocated from the range 61184..65519 for the lifetime of the service. They can be resolved using the new nss-systemd.so NSS module. The module must be enabled in /etc/nsswitch.conf. Services started in this way have PrivateTmp= and RemoveIPC= enabled, so that any resources allocated by the service will be cleaned up when the service exits. They also have ProtectHome=read-only and ProtectSystem=strict enabled, so they are not able to make any permanent modifications to the system.