diff --git a/README.md b/README.md
index 051b0ee..ee58e19 100644
--- a/README.md
+++ b/README.md
@@ -1,3 +1,5 @@
+<!---   THIS FILE IS AUTOMATICALLY GENERATED, DO NOT CHANGE IT BY HAND   --->
+
 stb
 ===
 
diff --git a/tools/make_readme.c b/tools/make_readme.c
index 03c9060..224f289 100644
--- a/tools/make_readme.c
+++ b/tools/make_readme.c
@@ -10,6 +10,8 @@ int main(int argc, char  **argv)
    char **list  = stb_stringfile("README.list", &listlen);  // stb_stringfile - read file lines into malloced array of strings
 
    FILE *f = fopen("../README.md", "wb");
+
+   fprintf(f, "<!---   THIS FILE IS AUTOMATICALLY GENERATED, DO NOT CHANGE IT BY HAND   --->\n\n");
    fwrite(header, 1, hlen, f);
 
    for (i=0; i < listlen; ++i) {