Write explicit bashrc file

img/builder.nix

@@ -32,6 +32,13 @@ let
     '';
     destination = "/etc/nix/nix.conf";
   };
+  bashrc = writeTextFile {
+    name = "bashrc";
+    text = ''
+      export PATH=${lib.makeBinPath contents}
+    '';
+    destination = "/etc/bashrc";
+  };
   contents = lib'.basePackages ++ [
     buildah
     (fakeNss.override {
@@ -52,9 +59,13 @@ let
   ];
 in
 lib'.mkImage {
-  inherit contents;
   name = name "builder";
-  config.Env = [ "TEMP=/tmp" "PATH=${lib.makeBinPath contents}" ];
+  config.Env = [
+    "TEMP=/tmp"
+    "PATH=${lib.makeBinPath contents}"
+  ];
+  # Set this explicitly so that we avoid infinite recursion
+  contents = contents ++ [ bashrc ];
   extraCommands = ''
     mkdir -p tmp
     mkdir -p var/tmp