diff --git a/src/fastjet/version.py b/src/fastjet/version.py
index 14e304aa..713ccffe 100644
--- a/src/fastjet/version.py
+++ b/src/fastjet/version.py
@@ -2,7 +2,7 @@
 
 import re
 
-__version__ = "3.4.2.0"
+__version__ = "3.4.2.1"
 version = __version__
 version_info = tuple(re.split(r"[-\.]", __version__))