Given the CentOS shit, I'm not convinced jumping from Docker Inc to RedHat is appropriately mitigating the risk of a corporate rug pull once they've decided its time for the next step in their enshittification plan...
It started as a CoreOS project and for a long time it was the only ebterprisey registry, and it included security scanning. Had some availability issues some time ago, but AFAIK today it's pretty good.
If you want actual reproducable, actual portable software, Nix. Otherwise there are countless other OCI runtimes, cri-o, containers, etc. Kubernetes doesn't even use Docker.
What a thing, docker. I can't get over the staying power it has had despite... Everything.
I'm not certain what "ecosystem" means in this context, but you can build docker images using Nix. It's actually pretty cool because the image only contains the runtime dependencies of whatever you throw in the container. No package manager or build system is included. I've only tinkered with Nix, nothing in my professional life, so YMMV.
I'm super interested in the ecosystem you mean here. I'm assuming that you mean ecosystem around images like kubernetes, ECS, etc like the other commenter guessed?
If so, I think Nix being able to create docker images addresses that specific concern.
I can easily install many apps hosted at the Docker hub but how would I achieve that without Docker hub, unless everyone starts hosting things elsewhere but that'll take a good while assuming the community's consensus is to ditch Docker altogether.
Or do you mean run as in "use docker image(s) within a nix expression". Like if you have a webapp with a nix devshell but want to start the docker postgres container for development?