diff --git a/tests/modules/programs/scmpuff/no-shell.nix b/tests/modules/programs/scmpuff/no-shell.nix
index df851767..96314e7a 100644
--- a/tests/modules/programs/scmpuff/no-shell.nix
+++ b/tests/modules/programs/scmpuff/no-shell.nix
@@ -10,6 +10,9 @@
       zsh.enable = true;
     };
 
+    nixpkgs.overlays =
+      [ (self: super: { zsh = pkgs.writeScriptBin "dummy" ""; }) ];
+
     nmt.script = ''
       assertFileNotRegex home-files/.zshrc '${pkgs.scmpuff} init -s'
       assertFileNotRegex home-files/.bashrc '${pkgs.scmpuff} init -s'
diff --git a/tests/modules/programs/scmpuff/no-zsh.nix b/tests/modules/programs/scmpuff/no-zsh.nix
index 18480add..90e0034b 100644
--- a/tests/modules/programs/scmpuff/no-zsh.nix
+++ b/tests/modules/programs/scmpuff/no-zsh.nix
@@ -8,6 +8,9 @@
       zsh.enable = true;
     };
 
+    nixpkgs.overlays =
+      [ (self: super: { zsh = pkgs.writeScriptBin "dummy" ""; }) ];
+
     nmt.script = ''
       assertFileNotRegex home-files/.zshrc '${pkgs.scmpuff} init -s'
     '';
diff --git a/tests/modules/programs/scmpuff/zsh.nix b/tests/modules/programs/scmpuff/zsh.nix
index d6f7cc5e..b27f6ca8 100644
--- a/tests/modules/programs/scmpuff/zsh.nix
+++ b/tests/modules/programs/scmpuff/zsh.nix
@@ -5,6 +5,9 @@
       zsh.enable = true;
     };
 
+    nixpkgs.overlays =
+      [ (self: super: { zsh = pkgs.writeScriptBin "dummy" ""; }) ];
+
     nmt.script = ''
       assertFileExists home-files/.zshrc
       assertFileContains \