The nixos/nix docker image on dockerhub fails if you follow the directions on dockerhub

[MatrixManAtYrService]

Describe the bug

Try to build this Dockerfile:

FROM nixos/nix
RUN nix-channel --update

As described here: https://hub.docker.com/r/nixos/nix

It fails with this error:

❯ docker build .
Sending build context to Docker daemon  504.6MB
Step 1/4 : FROM nixos/nix
 ---> 6f3d9e4c45a3
Step 2/4 : RUN whoami
 ---> Running in b9b9306ce3a1
root
Removing intermediate container b9b9306ce3a1
 ---> cd69d0600a6d
Step 3/4 : RUN nix-channel --update
 ---> Running in a7b8a55e7f53
error: Operation not permitted

Expected behavior

nix-channel --update is executable by the default image user (root)

nix-env --version output

I don't know, I can't run that either

Additional context

Found while trying to create a dockerfile which replicates this airflow bug: https://github.com/apache/airflow/issues/25330

[zagy]

It seems to have broken with 2.10.0. With 2.9.0 it still works.

[thufschmitt]

I can't reproduce with 2.10.0 either (same hash as the one in the issue) :thinking: Any idea what might cause the different behaviors?