diff --git a/lib/mackup.sh b/lib/mackup.sh
index 1e6aed8..1608264 100644
--- a/lib/mackup.sh
+++ b/lib/mackup.sh
@@ -80,6 +80,21 @@ _SSR_MACKUP_SKIP=(
     # Docker / VM infrastructure (large, or require special handling)
     .vagrant .minikube .kube .helm
 
+    # Dot-dirs that belong to apps already covered by a Mackup built-in,
+    # even when the built-in covers a different path (e.g. Library/Preferences
+    # or Library/Application Support) rather than the dot-dir itself.
+    # Adding them here prevents duplicate / redundant ssr-*.cfg suggestions.
+    .iterm2         # iterm2.cfg covers Library/Preferences + .config/iterm2
+    .vscode         # vscode.cfg covers Library/Application Support/Code/User
+    .vscode-insiders # vscode-insiders.cfg covers Library/Application Support/Code - Insiders
+    .zsh            # zsh.cfg covers .zshrc, .zshenv, .zprofile, .zlogin, .zlogout
+    .bash           # bash.cfg covers .bashrc, .bash_profile, .bash_logout etc.
+    .fish           # fish.cfg covers .config/fish
+
+    # Sync-service data directories — never back up a sync engine inside iCloud
+    .dropbox        # Dropbox data; backing up to iCloud would be circular
+    .OneDrive       # OneDrive data directory
+
     # History files (session-specific, not config)
     .bash_history .zsh_history .zsh_sessions .sh_history
     .lesshst .wget-hsts .python_history .node_repl_history