diff --git a/README.md b/README.md
index 63b05fa..e900ea6 100644
--- a/README.md
+++ b/README.md
@@ -20,6 +20,14 @@
 
 # Deployment
 
+Building the playground Docker container takes more than the default 10 minute time limit of cloud build, so increase its timeout first (note, `app/cloud_build_timeout` is a global configuration value):
+
+```
+gcloud config set app/cloud_build_timeout 1200  # 20 mins
+```
+
+Then:
+
 ```
 gcloud --project=golang-org --account=person@example.com app deploy app.yaml
 ```