diff --git a/tools/extract-changes.hs b/tools/extract-changes.hs
old mode 100644
new mode 100755
index 8c8160c2c..0a7f2a8cf
--- a/tools/extract-changes.hs
+++ b/tools/extract-changes.hs
@@ -1,3 +1,6 @@
+#!/usr/bin/env stack
+-- stack --stack-yaml=stack.yaml runghc --package pandoc-types
+
 -- Extract changes from latest version in changelog.
 import Text.Pandoc.JSON