Isn't disk cloning quite different from snapshot? I'm asking for learning purposes. I've used Clonezilla for a decade now and it has developed into a superior beast. None of the commercial products can beat it.
Assuming this is an option for you, convert your ext4 partition to btrfs (can be done without data loss) and enjoy having proper snapshot support. Timeshift makes it really easy to automate and manage btrfs snapshots.