diff --git a/libc/platform/bionic/page.h b/libc/platform/bionic/page.h
index a75b3ac..15ad4c5 100644
--- a/libc/platform/bionic/page.h
+++ b/libc/platform/bionic/page.h
@@ -32,6 +32,14 @@
 #endif
 }
 
+constexpr size_t max_page_size() {
+#if defined(PAGE_SIZE)
+  return PAGE_SIZE;
+#else
+  return 65536;
+#endif
+}
+
 // Returns the address of the page containing address 'x'.
 inline uintptr_t page_start(uintptr_t x) {
   return x & ~(page_size() - 1);