A Dockerfile does not describe a container. A Dockerfile describes how to build a container image. Running that image creates a container.

You can create images in other ways than Docker or Dockerfiles (ocra-build, img). Other programs can run container images (runc, containerd).

For example, Google's BLAZE/BAZEL build software can directly output a container image (and upload it to a registry) and then you can run that with runc on any platform and you haven't touched Docker or a Dockerfile once.