diff --git a/flaskr/__init__.py b/flaskr/__init__.py
index 521424d..a00cc28 100644
--- a/flaskr/__init__.py
+++ b/flaskr/__init__.py
@@ -28,7 +28,7 @@ def optimize_css_file():
 
 
 def create_app(test_config=None):
-    optimize_css()
+    optimize_css_file()
 
     app = Flask(__name__, instance_relative_config=True)
     app.config.from_mapping(