diff --git a/Casks/p/pacifist.rb b/Casks/p/pacifist.rb
index 3e4db2e5f2..6561887e02 100644
--- a/Casks/p/pacifist.rb
+++ b/Casks/p/pacifist.rb
@@ -13,6 +13,7 @@ cask "pacifist" do
   end
 
   auto_updates true
+  depends_on macos: ">= :mojave"
 
   app "Pacifist.app"