How to make systemctl on arch linux start mariadb (mysql) with the --skip-grant-tables flag

I have had the opportunity to familiarize myself with mariadb lately. Mariadb is an open source clone of the popular mysql relational database - now owned by oracle. It was very easy to get up and running on arch linux. Just a matter of:

sudo pacman -S mariadb
sudo systemctl enable mysqld

and it was up and running. However after a while I was unable to log on with the command line tool. I learned how to start the database with the --skip-grant-tables and found out that the user table mariadb uses for authentication was empty. Since my use of mariadb is only temporary I decided to not care so much about why this happen. Instead I decided to make sure that the database always starts with the mentioned flag. To do this you need to find the files systemctl uses for managing its tasks. They (some of them at least) are located in /usr/lib/systemd/system. There seems to be one file for each thing systemctl is managing. I found mysqld.service and added the --skip-grant-tables flag to the ExecStart key. Like this:

ExecStart=/usr/bin/mysqld --pid-file=/run/mysqld/mysqld.pid --skip-grant-tables 

So now my database starts without wanting authentication for connections. This is practical in a local development environment but should of course never be used in production.