Add a whatsnew entry

gpshead · gpshead · commit 060dbf5ee1ef · 2025-12-29T00:46:11.000Z
diff --git a/Doc/whatsnew/3.15.rst b/Doc/whatsnew/3.15.rst
@@ -428,6 +428,12 @@ argparse
   inline code when color output is enabled.
   (Contributed by Savannah Ostrowski in :gh:`142390`.)
 
+base64 & binascii
+-----------------
+
+* CPython's underlying base64 implementation now encodes 2x faster and decodes 3x
+  faster thanks to simple CPU pipelining optimizations.
+
 calendar
 --------
 
