diff --git a/Casks/lstk.rb b/Casks/lstk.rb
index ff1ab5c..0211fcd 100644
--- a/Casks/lstk.rb
+++ b/Casks/lstk.rb
@@ -36,9 +36,9 @@
   fish_completion "completions/lstk.fish"
   zsh_completion "completions/lstk.zsh"
 
-  postflight do
-    if OS.mac?
-      system_command "/usr/bin/xattr", args: ["-dr", "com.apple.quarantine", "#{staged_path}/lstk"]
+  postflight_steps do
+    on_macos do
+      run "/usr/bin/xattr", args: ["-dr", "com.apple.quarantine", "{{staged_path}}/lstk"]
     end
   end