- Navigate in your Home Assistant frontend to Settings -> Add-ons -> Add-on Store.
- In the ... menu at the top right corner click Repositories, add
https://github.com/lmagyar/homeassistant-addon-mariadb-inmemory
as repository. - Find the "In-memory MariaDB" add-on and click it. If it doesn't show up, wait until HA refreshes the information about the add-on, or click Check for updates in the ... menu at the top right corner.
- Click on the "INSTALL" button.
For more details, please see the add-on's Info and Documentation pages.