Creating a new image with umoci is fairly simple, and effectively involves creating an image “husk” which you can then operate on as though it was a normal image. New images contain no layers, and have a dummy configuration that should be replaced by a user.
If you wish to create a new image layout (which contains nothing except the
bare minimum to specify that the image is an OCI image), you can do so with
% umoci init --layout new_image
If you wish to create a new image inside the image layout, you can do so with
% umoci new --image new_image:new_tag