diff --git a/tools/generate.go b/tools/generate.go
index 700f447..ee5db8d 100644
--- a/tools/generate.go
+++ b/tools/generate.go
@@ -261,7 +261,8 @@ func renderIndex(examples []*Example) {
     check(err)
     indexF, err := os.Create(siteDir + "/index.html")
     check(err)
-    indexTmpl.Execute(indexF, examples)
+    err = indexTmpl.Execute(indexF, examples)
+    check(err)
 }
 
 func renderExamples(examples []*Example) {