Sync and encrypt folders?

I'd like to sync a folder (with many subfolders and files) with a destination folder, but *encrypt* the files in the destination folder.
The use case is that the destination folder would used as the source for a cloud backup, so I'd like to have the files encrypted before they move to the cloud.
I only want to (re)encrypted new/modified files, so that the cloud sync only needs to upload the changed delta.
Is this possible with Hazel? I couldn't see any encryption actions. Would I have to write a custom JavaScript action (or something similar)?
And, can it handle sync a large volume of files? Not sure if that's a use case for it or if I'd be pushing it too far.
The use case is that the destination folder would used as the source for a cloud backup, so I'd like to have the files encrypted before they move to the cloud.
I only want to (re)encrypted new/modified files, so that the cloud sync only needs to upload the changed delta.
Is this possible with Hazel? I couldn't see any encryption actions. Would I have to write a custom JavaScript action (or something similar)?
And, can it handle sync a large volume of files? Not sure if that's a use case for it or if I'd be pushing it too far.