diff --git a/Ruby/lib/terminal_notifier/guard/failed.rb b/Ruby/lib/terminal_notifier/guard/failed.rb
index e45863d..be5af39 100644
--- a/Ruby/lib/terminal_notifier/guard/failed.rb
+++ b/Ruby/lib/terminal_notifier/guard/failed.rb
@@ -1,7 +1,11 @@
 module TerminalNotifier
   module Guard
     module Failed
-      BIN_PATH = File.expand_path('../../../../vendor/terminal-notifier-failed.app/Contents/MacOS/terminal-notifier', __FILE__)
+      terminal_notifier_path = `which terminal-notifier`
+      BIN_PATH = terminal_notifier_path.empty? ?
+        File.expand_path('../../../../vendor/terminal-notifier-failed.app/Contents/MacOS/terminal-notifier', __FILE__)
+        :
+        terminal_notifier_path
     end
   end
 end
diff --git a/Ruby/lib/terminal_notifier/guard/notify.rb b/Ruby/lib/terminal_notifier/guard/notify.rb
index 86d1c4f..1619a7e 100644
--- a/Ruby/lib/terminal_notifier/guard/notify.rb
+++ b/Ruby/lib/terminal_notifier/guard/notify.rb
@@ -1,7 +1,11 @@
 module TerminalNotifier
   module Guard
     module Notify
-      BIN_PATH = File.expand_path('../../../../vendor/terminal-notifier-notify.app/Contents/MacOS/terminal-notifier', __FILE__)
+      terminal_notifier_path = `which terminal-notifier`
+      BIN_PATH = terminal_notifier_path.empty? ?
+        File.expand_path('../../../../vendor/terminal-notifier-failed.app/Contents/MacOS/terminal-notifier', __FILE__)
+        :
+        terminal_notifier_path
     end
   end
 end
diff --git a/Ruby/lib/terminal_notifier/guard/pending.rb b/Ruby/lib/terminal_notifier/guard/pending.rb
index 8634741..771a493 100644
--- a/Ruby/lib/terminal_notifier/guard/pending.rb
+++ b/Ruby/lib/terminal_notifier/guard/pending.rb
@@ -1,7 +1,11 @@
 module TerminalNotifier
   module Guard
     module Pending
-      BIN_PATH = File.expand_path('../../../../vendor/terminal-notifier-pending.app/Contents/MacOS/terminal-notifier', __FILE__)
+      terminal_notifier_path = `which terminal-notifier`
+      BIN_PATH = terminal_notifier_path.empty? ?
+        File.expand_path('../../../../vendor/terminal-notifier-failed.app/Contents/MacOS/terminal-notifier', __FILE__)
+        :
+        terminal_notifier_path
     end
   end
 end
diff --git a/Ruby/lib/terminal_notifier/guard/success.rb b/Ruby/lib/terminal_notifier/guard/success.rb
index b4cd9f0..9444a97 100644
--- a/Ruby/lib/terminal_notifier/guard/success.rb
+++ b/Ruby/lib/terminal_notifier/guard/success.rb
@@ -1,7 +1,11 @@
 module TerminalNotifier
   module Guard
     module Success
-      BIN_PATH = File.expand_path('../../../../vendor/terminal-notifier-success.app/Contents/MacOS/terminal-notifier', __FILE__)
+      terminal_notifier_path = `which terminal-notifier`
+      BIN_PATH = terminal_notifier_path.empty? ?
+        File.expand_path('../../../../vendor/terminal-notifier-failed.app/Contents/MacOS/terminal-notifier', __FILE__)
+        :
+        terminal_notifier_path
     end
   end
 end