diff --git a/src/asm/lexer.c b/src/asm/lexer.c
index 146dd2c5..d5cfa1c1 100644
--- a/src/asm/lexer.c
+++ b/src/asm/lexer.c
@@ -19,7 +19,9 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#ifndef _MSC_VER
 #include <unistd.h>
+#endif
 
 #include "extern/utf8decoder.h"
 #include "platform.h" /* For `ssize_t` */