diff --git a/src/prim/wasi/prim.c b/src/prim/wasi/prim.c
index 891c7123..0c9b31ed 100644
--- a/src/prim/wasi/prim.c
+++ b/src/prim/wasi/prim.c
@@ -7,6 +7,8 @@ terms of the MIT license. A copy of the license can be found in the file
 
 // This file is included in `src/prim/prim.c`
 
+#include <stdio.h>
+
 #include "mimalloc.h"
 #include "mimalloc/internal.h"
 #include "mimalloc/atomic.h"