diff --git a/build.sh b/build.sh
index 6d57648..7766c95 100755
--- a/build.sh
+++ b/build.sh
@@ -1,8 +1,6 @@
 #!/usr/bin/env bash
 set -eu
 clang generate.c -o generate -std=gnu2x -g
-./generate
 rm -rf public || true
-mkdir public
+./generate
 cp -r pdf public/pdf
-cp index.html public/index.html
diff --git a/generate.c b/generate.c
index a9d6f39..4c47473 100644
--- a/generate.c
+++ b/generate.c
@@ -1,5 +1,6 @@
 #include <sys/mman.h>
 #include <sys/ptrace.h>
+#include <sys/stat.h>
 #include <fcntl.h>
 #include <unistd.h>
 
@@ -365,7 +366,9 @@ fn void write_document(Writer* writer)
 
 int main()
 {
-    int fd = open("index.html", O_TRUNC | O_WRONLY | O_CREAT, 0644);
+    let(mkdir_result, mkdir("public", 0755));
+    assert(mkdir_result == 0);
+    int fd = open("public/index.html", O_TRUNC | O_WRONLY | O_CREAT, 0644);
     assert(fd >= 0);
     Writer writer = {};
     write_document(&writer);