diff --git a/.circleci/config.yml b/.circleci/config.yml
index 2e9130367..da69f5618 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -60,7 +60,7 @@ jobs:
           paths:
             - ./emsdk/emsdk
             - ~/.ccache
-          key: v1-emsdk-{{ checksum "emsdk/Makefile" }}-v6
+          key: v1-emsdk-{{ checksum "emsdk/Makefile" }}-v6-{{ .BuildNum }}
 
       - run:
           name: test