diff --git a/2015/day-01/README.org b/2015/day-01/README.org
index 85efc3b..cc36ad9 100644
--- a/2015/day-01/README.org
+++ b/2015/day-01/README.org
@@ -1,3 +1,3 @@
 #+begin_src sh
-  gforth main.fs
+  ./main.fs
 #+end_src
diff --git a/2015/day-01/main.fs b/2015/day-01/main.fs
old mode 100644
new mode 100755
index 1c9aa90..d196542
--- a/2015/day-01/main.fs
+++ b/2015/day-01/main.fs
@@ -1,3 +1,5 @@
+#! /usr/bin/env gforth
+
 : parse-instructions ( ulen addr  -- )
     0 >r
     0 u+do