diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index fb593d5..550985a 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -11,7 +11,7 @@ jobs:
     steps:
       - name: Set current date as env variable
         id: tagname
-        run: echo "timestamp=$(date +'%s')" >> GITHUB_OUTPUT
+        run: echo "timestamp=$(date +'%s')" >> $GITHUB_OUTPUT
 
       - uses: actions/checkout@v4
       - name: Install devbox