For clone this is possible already, by passing additional options to git clone: datalad clone <url> -c annex.private=true.

This would also be useful for create, e.g. when setting up a mostly read-only dataset in a temporary location.
Appending additional options to the git command does not work here, because they are added at the wrong position.

This would also be useful for create, e.g. when setting up a mostly read-only dataset in a temporary location. Appending additional options to the git command does not work here, because they are added at the wrong position.

It seems to be doable already too:

% datalad -c annex.private=true create dummy
% cat dummy/.git/config
...
[annex]
        uuid = f1eb3d37-0251-4510-bc98-ad2a7b2fcb55
        version = 8
        private = true
...

However, this way of passing the config item does not work for clone. The resulting heterogeneity is undesirable.

Though at first glance the above doesn't fully work (trying on DataLad 0.17.10):

❱ datalad -c annex.private=true create dummy
❱ cd dummy 
❱ cat .git/config
...
[annex]
	uuid = 1245a968-4d01-4280-be8d-cc2cf66e9c96
	version = 10
	private = true
...
❱ git cat-file blob git-annex:uuid.log
1245a968-4d01-4280-be8d-cc2cf66e9c96 mszczepanik@bnbnb64:~/dummy timestamp=1673436462.930674266s
❱ ls .git/annex/journal-private
ls: cannot access '.git/annex/journal-private': No such file or directory

Can't see why, could that be due to the internal order of things within create; or did I simply make a mistake?

Edit: I think that's because of the order in which things happen within create. The config overrides are applied after _setup_annex_repo, thus after git annex init; but private mode requires the config option to be set for git repo before git annex init.

I am finishing a PR (above) in which I propose introducing --reckless private for clone & get and introducing a --private option for create. We can of course disciss whether that's an appropriate naming/interface.

Yes, I can confirm too that I concluded to quickly. The config is set, but too late to have an impact on git annex init.