diff --git a/.circleci/config.yml b/.circleci/config.yml
index 0504f020..4335d887 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -86,7 +86,7 @@ workflows:
             branches:
               only: |
                 master
-                /^+([0-9])?(.{+([0-9]),x}).x/
+                /^\d+\.(?:\d+|x)(?:\.x)?$/
           requires:
             - test
             - lint