diff --git a/include/usearch/index.hpp b/include/usearch/index.hpp
index 4fe87109c..e8a79ba89 100644
--- a/include/usearch/index.hpp
+++ b/include/usearch/index.hpp
@@ -42,7 +42,8 @@
 #endif
 
 // Inferring hardware bitness: 32 vs 64
-#if __WORDSIZE == 64
+// https://stackoverflow.com/a/5273354
+#if UINTPTR_MAX == 0xffffffff
 #define USEARCH_64BIT_ENV
 #else
 #define USEARCH_32BIT_ENV