Different error this time after appending :test and doing an update.
2019-08-02 13:10:16,213 DEBG fd 8 closed, stopped monitoring <POutputDispatcher at 23375073562296 for <Subprocess at 23375073562408 with name urbackup in state STARTING> (stdout)>
2019-08-02 13:10:16,213 DEBG fd 10 closed, stopped monitoring <POutputDispatcher at 23375073656112 for <Subprocess at 23375073562408 with name urbackup in state STARTING> (stderr)>
2019-08-02 13:10:16,213 INFO exited: urbackup (exit status 127; not expected)
2019-08-02 13:10:16,214 DEBG received SIGCHLD indicating a child quit
2019-08-02 13:10:19,218 INFO spawned: 'urbackup' with pid 72
2019-08-02 13:10:19,230 DEBG 'urbackup' stderr output:
/usr/bin/urbackupsrv: error while loading shared libraries: libcryptopp.so.7: cannot open shared object file: No such file or directory