diff --git a/src/spectator/matchers/matchable.cr b/src/spectator/matchers/matchable.cr
index 877bf666..11019f4d 100644
--- a/src/spectator/matchers/matchable.cr
+++ b/src/spectator/matchers/matchable.cr
@@ -82,6 +82,10 @@ module Spectator::Matchers
         no_block!
       end
 
+      def does_not_match?(&block)
+        !matches?(&block)
+      end
+
       def failure_message(actual_value)
         no_block!
       end