diff --git a/README.md b/README.md
index aba12cb..706d55f 100644
--- a/README.md
+++ b/README.md
@@ -16,7 +16,7 @@ Build it:
 
 In your `${HOME}/.bubble-test.env` file, add this line (fix the path to point to the correct location of your `bubble-web/dist` directory):
 
-    export ASSETS_DIR=/path/to/bubble-web/dist
+    export BUBBLE_ASSETS_DIR=/path/to/bubble-web/dist
 
 In the `bubble/bubble-server` directory, run the test named `bubble.test.dev.DevServerTest`, like so: