diff --git a/runtime/compiletime/memory/64bit_nix.c b/runtime/compiletime/memory/64bit_nix.c
index cd5bb68..db85276 100644
--- a/runtime/compiletime/memory/64bit_nix.c
+++ b/runtime/compiletime/memory/64bit_nix.c
@@ -1,4 +1,6 @@
 /* https://github.com/gwsystems/silverfish/blob/master/runtime/memory/64bit_nix.c */
+
+#include <assert.h>
 #include "types.h"
 
 #ifdef USE_MEM_VM