diff --git a/Makefile b/Makefile
index 800b1eab..9fd64095 100644
--- a/Makefile
+++ b/Makefile
@@ -33,6 +33,8 @@ endif
 
 # when MU_HACKER is set, do a debug build
 # MU_HACKER is for djcb & compatible developers
+# note that mu uses C++17, we only pass C++20 here
+# for the better error messages (esp. for fmt).
 ifneq (${MU_HACKER},)
 MESON_FLAGS:=$(MESON_FLAGS) '-Dbuildtype=debug'    \
 			    '-Db_sanitize=address' \
diff --git a/meson.build b/meson.build
index 4742958d..7694025e 100644
--- a/meson.build
+++ b/meson.build
@@ -17,7 +17,7 @@
 ################################################################################
 # project setup
 project('mu', ['c', 'cpp'],
-        version: '1.11.8',
+        version: '1.11.9',
         meson_version: '>= 0.56.0',
         license: 'GPL-3.0-or-later',
         default_options : [