diff --git a/resource_embedder.c b/resource_embedder.c
index 9cc2b56..2a28bde 100644
--- a/resource_embedder.c
+++ b/resource_embedder.c
@@ -2,6 +2,7 @@
 #include <string.h>
 #include <stdbool.h>
 #include <stdlib.h>
+#include <stdint.h>
 
 // the program writes generated text to stdout
 // other messages must be sent to stderr
@@ -120,11 +121,12 @@ void process_file(const char* input_file_path,
         free(_sp1);
         fprintf(out_file,
             "#pragma once\n"
+            "#include <stdint.h>\n"
             "\n"
             "typedef struct {\n"
             "    const char* path;\n"
             "    const char* data;\n"
-            "    const unsigned long long size;\n"
+            "    int32_t size;\n"
             "} EmbeddedResource;\n"
             "\n"
             "#define RSCAT(A,B,C...) A##B##C"