diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 261e7a63..307ef82b 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -31,7 +31,7 @@ jobs:
     strategy:
       matrix:
         node-version:
-          - 18.x
+          - 16.x
     steps:
       - uses: actions/checkout@v3
       - uses: actions/setup-node@v3
diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 03ddc999..17748f02 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -27,7 +27,7 @@ jobs:
     strategy:
       matrix:
         node-version:
-          - 18.x
+          - 16.x
     steps:
       - uses: actions/checkout@v3
       - uses: actions/setup-node@v3
diff --git a/app/app.yaml b/app/app.yaml
index 51c3b3f6..7f23e1be 100644
--- a/app/app.yaml
+++ b/app/app.yaml
@@ -12,7 +12,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-runtime: nodejs18
+runtime: nodejs16
 handlers:
 # Serve all static files with url ending with a file extension
 - url: /(.*\..+)$