diff --git a/src/libcmd/markdown.hh b/src/libcmd/markdown.hh
index 164f99b98..66db1736c 100644
--- a/src/libcmd/markdown.hh
+++ b/src/libcmd/markdown.hh
@@ -1,7 +1,7 @@
 #pragma once
 ///@file
 
-#include "types.hh"
+#include <string_view>
 
 namespace nix {