diff --git a/README.md b/README.md
index b852a4a2d..01ca6b799 100644
--- a/README.md
+++ b/README.md
@@ -29,7 +29,7 @@ set up the snapshot script:
 start the workers:
 
 ```
-python -m workers.diffsworker -D
+STACK=prod python -m workers.diffsworker -D
 ```
 
 bouncing the servers: