diff --git a/.github/workflows/update-casks.yml b/.github/workflows/update-casks.yml
index cb984038..8c689484 100644
--- a/.github/workflows/update-casks.yml
+++ b/.github/workflows/update-casks.yml
@@ -50,7 +50,7 @@ jobs:
         uses: actions/checkout@v2
         with:
           repository: jimeh/build-emacs-for-macos
-          ref: "v0.6.20"
+          ref: "v0.6.21"
           path: builder
       - uses: actions/setup-go@v2
         with: