diff --git a/artiq/windows/default.nix b/artiq/windows/default.nix
index 7e7d190..8b21a85 100644
--- a/artiq/windows/default.nix
+++ b/artiq/windows/default.nix
@@ -17,7 +17,7 @@ in
 
 stdenv.mkDerivation {
   name = "windows-test";
-  src = ./.;
+  src = null;
 
   phases = [ "installPhase" "checkPhase" ];
   installPhase = "touch $out";
diff --git a/main.nix b/main.nix
index 517e000..ea6a6e1 100644
--- a/main.nix
+++ b/main.nix
@@ -55,8 +55,7 @@ in
 
     windows-no-hardware-tests = pkgs.stdenv.mkDerivation {
       name = "windows-no-hardware-tests";
-      # dummy src
-      src = generatedNix;
+      src = null;
       buildInputs = [ (windowsRunner {}) ];
       phases = [ "buildPhase" ];
       buildPhase = ''