diff --git a/api/build.sh b/api/build.sh
index a3f129d0e..00965d3b0 100644
--- a/api/build.sh
+++ b/api/build.sh
@@ -7,7 +7,7 @@
 
 # Usage: bash build.sh <ee>
 
-git_sha1=$(git rev-parse HEAD)
+git_sha1=${IMAGE_TAG:-$(git rev-parse HEAD)}
 envarg="default-foss"
 check_prereq() {
     which docker || {