Garage is a S3 implementation that allows to easily serve websites as well. In their doc they show how to deploy SSGs to S3. Some implement this feature internally, other only implement exporting to a filesystem.
We could add this feature to Zola too.
Baking that into Zola is a mistake, imho. It’s the start of something monolithic.
Use a Makefile.
I do the following to rsync from my local machine to an AWS Lightsail machine. It will be somewhat similar.
rsync:
$(RSYNC) -av -e "ssh -i \"$(SSH_CERT_PATH)\"" $(OUT) $(USER)@$(HOST):$(DEST_PATH)
$(OUT) variable matches the local Zola build directory
Rsync is not supported but it is similar if you have the AWS CLI.
https://serverfault.com/questions/754690/rsync-to-aws-s3-bucket
https://superuser.com/questions/288270/can-i-use-rsync-for-backing-up-at-amazon-s3