~  sudo mkdir /var/lib/ekl-test-2                                                                                                                                                                    ~
[sudo] password for ekleog: 
 ~  echo "hello" | sudo tee /var/lib/ekl-test-2/foobar                                                                                                                                                ~
hello
 ~  sudo systemd-run --pty --property=DynamicUser=yes --property=StateDirectory=ekl-test-2 cat /var/lib/ekl-test-2/foobar                                                                             ~
Running as unit: run-u1392780.service
Press ^] three times within 1s to disconnect TTY.
hello
 ~  ls -lah /var/lib                                                                                                                                                                              ~
total 12K
...
lrwxrwxrwx 1 root    root     18 Nov 12 23:56 ekl-test-2 -> private/ekl-test-2
...