Add EROFS filesystem as an alternative format

Hi developers,

I’m investigating app sandbox use cases for EROFS, and I wonder if it’s possible for snaps to add EROFS as an alternative way.

First, EROFS has been landed in main distros such as ubuntu, debian, fedora, opensuse, gentoo, WSL, etc.

Second, Curently EROFS can do incremental update between images with data deduplication in addition to compression. Laterly we’d also like to add self-contained verfication and encryption support.

Currently such incremental update approach is landed with Nydus image service for container images, also see. But I’d also like to develop this feature to erofs-utils if other use cases like app sandboxes need it.

Thanks, Gao Xiang