Unable to create docker image using dockertools

I’m attempting to build a docker image containing alpine and a haskell app I’m building but I’m getting the following error when I try to build the image:

jason/pkgs/aludrog >> nix-build docker.nix
these derivations will be built:
  /nix/store/pqyxb35xpgmj3jbi2ji3vnxlkjz1rgj3-aludrog-0.1.0.0.drv
  /nix/store/hp7adnsqd4jz4mlrngvxrpq7cmwkv4wd-aludrog-config.json.drv
  /nix/store/2g9dc52d7i3lj65whvm82460kd35b469-docker-layer-aludrog.drv
  /nix/store/4wr5cwci25x20cnrhpxzjh7ainmb06vl-runtime-deps.drv
  /nix/store/i1niaka5p34g53mkg1gmapkrhmr45b69-docker-image-alpine-3.11.tar.drv
  /nix/store/i1zm8f06qmadkg46zs9p2vgv9vqfjf58-docker-image-aludrog.tar.gz.drv
building '/nix/store/i1niaka5p34g53mkg1gmapkrhmr45b69-docker-image-alpine-3.11.tar.drv'...
building '/nix/store/pqyxb35xpgmj3jbi2ji3vnxlkjz1rgj3-aludrog-0.1.0.0.drv'...
FATA[0000] Error loading trust policy: open /etc/containers/policy.json: no such file or directory
builder for '/nix/store/i1niaka5p34g53mkg1gmapkrhmr45b69-docker-image-alpine-3.11.tar.drv' failed with exit code 1
cannot build derivation '/nix/store/i1zm8f06qmadkg46zs9p2vgv9vqfjf58-docker-image-aludrog.tar.gz.drv': 1 dependencies couldn't be built
error: build of '/nix/store/i1zm8f06qmadkg46zs9p2vgv9vqfjf58-docker-image-aludrog.tar.gz.drv' failed

Here’s my docker.nix file:

{ nixpkgs ? import <nixpkgs> {} }:
let
  aludrog-static = nixpkgs.haskell.lib.justStaticExecutables (nixpkgs.pkgs.haskellPackages.callCabal2nix "aludrog" ./. {});
  dockerImage =
    nixpkgs.pkgs.dockerTools.buildImage {
      name = "aludrog";
      tag = "latest";
      fromImage = nixpkgs.pkgs.dockerTools.pullImage {
          imageName = "alpine";
          finalImageTag = "3.11";
          imageDigest = "sha256:9a839e63dad54c3a6d1834e29692c8492d93f90c59c978c1ed79109ea4fb9a54";
          sha256 = "00lvm913qjk30szc2q8dkaa4h1sqvi044mbgw6xc6rxzfxfd8w0g";
      };
      contents = "${aludrog-static}/bin";
      config = {
        Cmd = [
          "${aludrog-static}/bin/aludrog"
        ];
      };
    };
in
  dockerImage

Any idea on how to resolve this?

I remember this error from skopeo:

FATA[0000] Error loading trust policy: open /etc/containers/policy.json: no such file or directory

However, I couldn’t reproduce the issue using nixpkgs revision 571212eb (after I replaced the references to aludrog-static). Maybe this commit has fixed it: dockerTools: fix skopeo commands · NixOS/nixpkgs@365d07c · GitHub

Thanks @utdemir! That commit did fix my problem.