Any chance of seeing a version of that guide outside of your organization?

The software is nice, if looking to run your own - I'd recommend it over the typical Docker-provided incantation

Way more enterprise appropriate, for example - granular control on caches

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.