@tsu2 this gives an interesting summery:
REPOSITORY TAG IMAGE ID CREATED SIZE registry.opensuse.org/opensuse/tumbleweed latest 1d71b22e34c0 38 hours ago 98.4MB registry.opensuse.org/opensuse/busybox latest e6641680f445 3 days ago 7.83MB bitnami/minideb buster 3b80e185d43d 7 days ago 67.5MB debian buster a8797652cfd9 2 weeks ago 114MB alpine 3.11 e7d92cdc71fe 4 weeks ago 5.59MB alpine latest e7d92cdc71fe 4 weeks ago 5.59MB busybox latest 6d5fcfe5ff17 7 weeks ago 1.22MB
The tumbleweed container image fits in size between a default default debian Buster and the bitnami optimized one, all of which should have relatively similar functionality for their respective platforms. A look inside the tumbleweed container did not suggest to me there was all that much that could be taken out of it, though. In any case, it is not a bad baseline size, and you can use zypper to install any arbitrary opensuse tumbleweed repo package (including those you might make on obs) into your container, much like one can do with apt-get on either of the debian ones.
The opensuse busybox image that Richard Brown suggested, on the other hand, is actually larger than a full alpine base image, and, without zypper, offers far less usable functionality than the alpine one. At only 5.6mb, the Alpine image is actually the rough equivalent in container functionality to the mini bitnami image (67mb) and the opensuse ?jeos? tumbleweed container (98mb).
Now maybe it is possible to create a JeOS-like opensuse container image that substitutes busybox and includes at least a “mini” version of zypper. I suspect it could come in either around or maybe even smaller than the bitnami optimized debian. Maybe a microos container would also be better, or either would be smaller by using different tools to externally build the image rather than carrying packaging inside the container image itself, and that could really easily be good enough since you can leverage obs. But I do not see that really approaching, let alone becoming smaller than alpine, as Brown was claiming as being already true with the existing opensuse busybox one. However, even the existing tumbleweed container base image, as is, at least does fairly well compared to Debian, even if not “bitnami” well. I could certainly see doing conventional opensuse containers with that (or a leap) base image instead of a Debian one.