diff --git a/runtests b/runtests
index 7066932..77a4c44 100755
--- a/runtests
+++ b/runtests
@@ -65,7 +65,7 @@ def _vet():
 
 
 def _toc():
-    _run('node_modules/.bin/markdown-toc -i README.md')
+    _run('bash node_modules/.bin/markdown-toc -i README.md')
     _run('git diff --quiet')