diff --git a/.circleci/config.yml b/.circleci/config.yml
index f63f21dd..3c82fb06 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -457,4 +457,4 @@ workflows:
             - test_unit
           filters:
             branches:
-              only: \d\.\d
+              only: /\d\.\d/