diff --git a/tests/modules/programs/lieer/lieer.nix b/tests/modules/programs/lieer/lieer.nix
index 3f1c8b688..1671f4f5e 100644
--- a/tests/modules/programs/lieer/lieer.nix
+++ b/tests/modules/programs/lieer/lieer.nix
@@ -13,6 +13,10 @@ with lib;
 
     accounts.email.accounts = { "hm@example.com".lieer.enable = true; };
 
+    nixpkgs.overlays = [
+      (self: super: { gmailieer = pkgs.writeScriptBin "dummy-gmailieer" ""; })
+    ];
+
     nmt.script = ''
       assertFileExists home-files/Mail/hm@example.com/.gmailieer.json
       assertFileContent home-files/Mail/hm@example.com/.gmailieer.json \
diff --git a/tests/modules/services/lieer/lieer-service.nix b/tests/modules/services/lieer/lieer-service.nix
index 3c9e66397..faef5053c 100644
--- a/tests/modules/services/lieer/lieer-service.nix
+++ b/tests/modules/services/lieer/lieer-service.nix
@@ -18,7 +18,9 @@ with lib;
 
     nixpkgs.overlays = [
       (self: super: {
-        gmailieer = super.gmailieer // { outPath = "@lieer@"; };
+        gmailieer = pkgs.writeScriptBin "dummy-gmailieer" "" // {
+          outPath = "@lieer@";
+        };
       })
     ];