diff --git a/nix/nix-daemon/nix-daemon.cc b/nix/nix-daemon/nix-daemon.cc
index ffac6cde34..1163a249d1 100644
--- a/nix/nix-daemon/nix-daemon.cc
+++ b/nix/nix-daemon/nix-daemon.cc
@@ -1,3 +1,4 @@
+#include "config.h"
 #include "shared.hh"
 #include "local-store.hh"
 #include "util.hh"