Incremental backup in mariaDB mysql
You might check out Percona's Xtrabackup solution and see if it will work with MariaDB as all seem to be drop-in replacements.

See: https://www.percona.com/doc/percona-xtrabackup/2.1/xtrabackup_bin/incremental_backups.html

Some articles imply this would work in MariaDB. I only use Percona so cannot confirm unfortunately: https://mariadb.com/kb/en/mariadb/backup-restore-and-import-xtrabackup/