diff --git a/ChangeLog b/ChangeLog
index b861ddda..093eeaf5 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+2022-08-27  Jay Berkenbilt  <ejb@ql.org>
+
+        * From m-holger: major refactoring of QPDFTokenizer to improve
+        readability and to optimize performance. This also included some
+        optimizations to some InputSource classes. Thanks for this
+        excellent contribution. Fixes #749, #442.
+
 2022-08-07  Jay Berkenbilt  <ejb@ql.org>
 
         * Add new build configuration option ENABLE_QTC, which is off by
diff --git a/manual/release-notes.rst b/manual/release-notes.rst
index ab2c1d8e..01a19249 100644
--- a/manual/release-notes.rst
+++ b/manual/release-notes.rst
@@ -11,7 +11,8 @@ For a detailed list of changes, please see the file
 
     - Many performance enhancements have been added. In developer
       performance benchmarks, gains on the order of 20% have been
-      observed.
+      observed. Most of that work, including major optimization of
+      qpdf's lexical layer, was done by M. Holger.
 
   - Replacement of ``PointerHolder`` with ``std::shared_ptr``