diff --git a/flake.lock b/flake.lock
new file mode 100644
index 0000000..f58a54b
--- /dev/null
+++ b/flake.lock
@@ -0,0 +1,48 @@
+{
+  "nodes": {
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1739736696,
+        "narHash": "sha256-zON2GNBkzsIyALlOCFiEBcIjI4w38GYOb+P+R4S8Jsw=",
+        "owner": "nixos",
+        "repo": "nixpkgs",
+        "rev": "d74a2335ac9c133d6bbec9fc98d91a77f1604c1f",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nixos",
+        "ref": "nixos-unstable",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "root": {
+      "inputs": {
+        "nixpkgs": "nixpkgs",
+        "wfvm": "wfvm"
+      }
+    },
+    "wfvm": {
+      "inputs": {
+        "nixpkgs": [
+          "nixpkgs"
+        ]
+      },
+      "locked": {
+        "lastModified": 1718082876,
+        "narHash": "sha256-u4OgfsO6jnQwHNmxHhSIfCKaa2gYoIYwGKPJFZSpK/A=",
+        "ref": "refs/heads/master",
+        "rev": "e811c7c5d87059cb93b6548109fcafb3268a3af1",
+        "revCount": 70,
+        "type": "git",
+        "url": "https://git.m-labs.hk/m-labs/wfvm"
+      },
+      "original": {
+        "type": "git",
+        "url": "https://git.m-labs.hk/m-labs/wfvm"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}
diff --git a/flake.nix b/flake.nix
index f7410cb..8d25155 100644
--- a/flake.nix
+++ b/flake.nix
@@ -2,6 +2,9 @@
   inputs = {
     nixpkgs.url = "github:nixos/nixpkgs/nixos-unstable";
     wfvm.url = "git+https://git.m-labs.hk/m-labs/wfvm";
+
+    # wfvm uses a very old branch of nixpkgs (2023-05-25)
+    wfvm.inputs.nixpkgs.follows = "nixpkgs";
   };
 
   outputs =
@@ -11,15 +14,15 @@
       wfvm,
     }:
     let
-      pkgs = import nixpkgs;
+      # import nixpkgs
+      pkgs = (import nixpkgs {});
     in
     {
-      packages."x86_64-linux".windows-vm = wfvm.lib.makeWindowsImage {
-        # configuration parameters go here
-        windowsImage = pkgs.requireFile {
-          name = "Tiny11_24H2_English_x64.iso";
+      packages."${pkgs.system}".windows-vm = wfvm.lib.makeWindowsImage {
+        windowsImage = (pkgs.fetchurl {
+          url = "file:///home/primary/Downloads/tiny11.iso";
           sha256 = "ea9cee512457c763484dbeaeee98caba8c2e69e0420bdae8c4508e31ad8ccd99";
-        };
+        });
 
         installCommands = [
           {