Colorize gem replaced with rainbow.

lib/system_check/helpers.rb

@@ -5,11 +5,12 @@ module SystemCheck
     # if we ever print anything in red - that's an error
     $check_failed = false
     class String
-
-      alias_method :orig_red, :red
-      def red(*args)
-        $check_failed = true
-        orig_red(*args)
+      alias_method :orig_color, :color
+      def color(code)
+        if code == :red
+          $check_failed = true
+        end
+        orig_color(code)
       end
     end
 

lib/system_check/simple_executor.rb

@@ -3,11 +3,12 @@ module SystemCheck
   # if we ever print anything in red - that's an error
   $check_failed = false
   class String
-
-    alias_method :orig_red, :red
-    def red(*args)
-      $check_failed = true
-      orig_red(*args)
+    alias_method :orig_color, :color
+    def color(code)
+      if code == :red
+        $check_failed = true
+      end
+      orig_color(code)
     end
   end