diff --git a/README.md b/README.md
index e1daccd..af023ae 100644
--- a/README.md
+++ b/README.md
@@ -10,5 +10,5 @@ Frontend
 
 The front end is located in root.  The meat of the logic is in
 `js/solardash.base.js`.  The testing infrastructure is in
-`js/solardash.file.js` as if you are launching the page from a file
+`js/solardash.file.jspp` as if you are launching the page from a file
 url, there is no way to make a url to access the backend.