diff --git a/Jenkinsfile b/Jenkinsfile
index 7044dbd..3567fcd 100644
--- a/Jenkinsfile
+++ b/Jenkinsfile
@@ -268,7 +268,7 @@ NODE
             sh '''
               set -eu
               . build/version.env
-              SHORT_SHA="$(git rev-parse --short HEAD)"
+              SHORT_SHA="$(printf '%s' "${GIT_COMMIT:-nohash}" | cut -c1-8)"
               IMAGE_TAG="${APP_VERSION}-${BUILD_NUMBER}-${SHORT_SHA}"
 
               printf '%s' "${HARBOR_PASSWORD}" | docker login registry.bstein.dev -u "${HARBOR_USERNAME}" --password-stdin