He used the FUSE (Filesystem in Userspace) interface in order to achieve “The Cloud Native Computer”, a storageless laptop.

All the technical details on https://ersei.net/en/blog/fuse-root

https://www.tomshardware.com/software/linux/dev-boots-a-pc-from-google-drive-storage-storage-less-laptop-becomes-a-truly-cloud-native-computer