Start MariaDB in GuixSD

$ mysqld
2017-02-14 17:32:17 3073330816 [Note] mysqld (mysqld 10.1.21-MariaDB) starting as process 18871 ...
2017-02-14 17:32:17 3073330816 [Warning] Can't create test file /var/lib/mysql/portatil.lower-test
mysqld: Can't change dir to '/var/lib/mysql/' (Errcode: 2 "No such file or directory")
2017-02-14 17:32:17 3073330816 [ERROR] Aborting