Unable to build podman compatiable containers using nix-build and dockerTools.buildImage - containers

Question

The following is invidious.nix, which builds a container that contains nix packages for Bash, Busybox and Invidious:
let
# nixos-22.05 / https://status.nixos.org/
pkgs = import (fetchTarball "https://github.com/NixOS/nixpkgs/archive/d86a4619b7e80bddb6c01bc01a954f368c56d1df.tar.gz") {};
in rec {
docker = pkgs.dockerTools.buildImage {
name = "invidious";
contents = [ pkgs.busybox pkgs.bash pkgs.invidious ];
config = {
Cmd = [ "/bin/bash" ];
Env = [];
Volumes = {};
};
};
}
If I try to load the container with docker load < result, Docker can correctly load the container.
docker load < result
14508d34fd29: Loading layer [==================================================>] 156.6MB/156.6MB
Loaded image: invidious:2nrcdxgz46isccfgyzdcbirs0vvqhp55
However, if I attempt the same thing using podman, I get the following error:
podman load < result
Error: payload does not match any of the supported image formats:
* oci: initializing source oci:/var/tmp/podman3824611648:: open /var/tmp/podman3824611648/index.json: not a directory
* oci-archive: loading index: open /var/tmp/oci1927542201/index.json: no such file or directory
* docker-archive: loading tar component manifest.json: archive/tar: invalid tar header
* dir: open /var/tmp/podman3824611648/manifest.json: not a directory
If I inspect the result, it does appear to have the correct format for an OCI container:
tar tvfz result
dr-xr-xr-x root/root 0 1979-12-31 19:00 ./
-r--r--r-- root/root 391 1979-12-31 19:00 027302622543ef251be6d3f2d616f98c73399d8cd074b0d1497e5a7da5e6c882.json
dr-xr-xr-x root/root 0 1979-12-31 19:00 669db3729b40e36a9153569b747788611e547f0b50a9f7d77107a04c6ddd887e/
-r--r--r-- root/root 3 1979-12-31 19:00 669db3729b40e36a9153569b747788611e547f0b50a9f7d77107a04c6ddd887e/VERSION
-r--r--r-- root/root 353 1979-12-31 19:00 669db3729b40e36a9153569b747788611e547f0b50a9f7d77107a04c6ddd887e/json
-r--r--r-- root/root 156579840 1979-12-31 19:00 669db3729b40e36a9153569b747788611e547f0b50a9f7d77107a04c6ddd887e/layer.tar
-r--r--r-- root/root 280 1979-12-31 19:00 manifest.json
-r--r--r-- root/root 128 1979-12-31 19:00 repositories
How do I get nix-build to create compliant containers that podman can read?
nix-build version: 2.10.3
podman version: 4.2.0

Answer 1

It turns out, the version of podman I'm running can't read gzipped tar files. The following works:
zcat result | podman load