diff --git a/stage0/spl_mcode.h b/stage0/spl_mcode.h
index 631c904..741aed6 100644
--- a/stage0/spl_mcode.h
+++ b/stage0/spl_mcode.h
@@ -9,8 +9,15 @@
 #include <stddef.h>
 #include <stdint.h>
 
+#ifndef SPL_USIZE_TYPEDEF
+#define SPL_USIZE_TYPEDEF
 typedef uintptr_t usize;
+#endif
+
+#ifndef SPL_ISIZE_TYPEDEF
+#define SPL_ISIZE_TYPEDEF
 typedef intptr_t isize;
+#endif
 
 typedef enum {
     SPL_VOID,
@@ -103,7 +110,7 @@ typedef enum {
 #define X(opcode, name, argc, pop, push, desc) opcode,
     SPL_OPCODES(X)
 #undef X
-    SPL_OPCODE_COUNT,
+        SPL_OPCODE_COUNT,
 } spl_vm_opcode_t;
 
 /*
@@ -192,8 +199,6 @@ void spl_prog_init(spl_prog_t *prog);
 void spl_prog_drop(spl_prog_t *prog);
 void spl_prog_dump(spl_prog_t *prog);
 
-
-
 int spl_prog_load_from_file(const char *fname, spl_prog_t *prog);
 int spl_prog_load_from_buffer(const char *buffer, usize len, spl_prog_t *prog);
 int spl_prog_store_to_file(const char *fname, spl_prog_t *prog);