Aion is built on top of Google Cloud Platform, specifically a G Suite account that is under our control (under collective ownership of Before the Beginning Inc.)
This allows us to leverage Google's scale and integration with many pre-existing workflows. Almost all current teachers in Aotearoa have a Google Account of some description, whether that be one that is offered through their school or one that they have personally.
Our G Suite backend has no storage limits, and can be mounted as an external filesystem on your computer so you can immediately access files from the Explorer or Finder app on your computer.
We also control an independent rclone server which creates back ups of everything on G Suite every 15 minutes. Should this account ever close, or something happens which forces Aion to close, this rclone server will remain active and distribute all Aion files via a magnet link.
In the future we wish to create another level of distribution by building a secondary backend on top of the Ethereum blockchain, so that there is no central authority controlling Aion and makes it virtually impossible for the system to ever go offline.