diff --git a/scripts/run-build.sh b/scripts/run-build.sh
index 118b9693830..8c15e147117 100755
--- a/scripts/run-build.sh
+++ b/scripts/run-build.sh
@@ -18,5 +18,6 @@ set -e
 
 DIR=$1
 if [[ -f "$DIR/run-ci" || "$NIGHTLY" = true ]]; then
-  gcloud builds submit . --config=$DIR/cloudbuild.yml
+  gcloud builds submit . --config=$DIR/cloudbuild.yml \
+    --substitutions _NIGHTLY=$NIGHTLY
 fi
diff --git a/tfjs-core/cloudbuild.yml b/tfjs-core/cloudbuild.yml
index 5872e71a53e..28d69c0b2ce 100644
--- a/tfjs-core/cloudbuild.yml
+++ b/tfjs-core/cloudbuild.yml
@@ -30,6 +30,7 @@ steps:
   waitFor: ['build']
   env: ['BROWSERSTACK_USERNAME=deeplearnjs1']
   secretEnv: ['BROWSERSTACK_KEY']
+  env: ['NIGHTLY=$_NIGHTLY']
 
 # Run unit tests in react native.
 - name: 'node:10'