Add builder image

pkgs/default.nix

@@ -1,4 +1,4 @@
-{ pkgs, ... }:
+{ pkgs, top, ... }:
 
 let
   c = pkgs.callPackage;
@@ -16,6 +16,7 @@ in
   inject-darwin = c ./inject-darwin.nix { };
   inject = c ./inject.nix { };
   img-bitwarden = c ./img-bitwarden.nix { };
+  img-builder = c ./img-builder.nix { inherit top; };
   img-immich = c ./img-immich.nix { };
   qemu-hook = c ./qemu-hook.nix { };
   setup-ssh = c ./setup-ssh { };

pkgs/img-builder.nix

@@ -0,0 +1,67 @@
+{
+  bashInteractive,
+  dockerTools,
+  git,
+  lib,
+  nix,
+  pkgs,
+  podman,
+  top,
+  writeShellApplication,
+  ...
+}:
+let
+  policy = (
+    pkgs.writeTextFile {
+      name = "policy.json";
+      text = ''
+        {
+          "default": [{"type": "insecureAcceptAnything"}]
+        }
+      '';
+      destination = "/etc/containers/policy.json";
+    }
+  );
+  activate = writeShellApplication {
+    name = "activate";
+    runtimeInputs = [ bashInteractive ];
+    text = ''
+      mkdir -p /etc/containers
+      cp ${policy}/etc/containers/policy.json /etc/containers/policy.json;
+      bash "$@"
+    '';
+  };
+in
+(import "${nix.src.outPath}/docker.nix" {
+  inherit pkgs;
+  name = "img-builder";
+  tag = "latest";
+
+  bundleNixpkgs = false;
+  Cmd = [
+    (lib.getExe activate)
+  ];
+  extraPkgs = [
+    dockerTools.caCertificates
+    podman
+  ];
+  flake-registry = (pkgs.formats.json { }).generate "flake-registry.json" ({
+    version = 2;
+    flakes.nixpkgs = {
+      exact = true;
+      from = {
+        id = "nixpkgs";
+        type = "indirect";
+      };
+      to = "${top.nixunstable}";
+    };
+  });
+  gitMinimal = git; # We want the full version in this
+  maxLayers = 111;
+  nixConf = {
+    experimental-features = [
+      "nix-command"
+      "flakes"
+    ];
+  };
+})