diff --git a/ms2pip/__init__.py b/ms2pip/__init__.py
index e558157..ec27b18 100644
--- a/ms2pip/__init__.py
+++ b/ms2pip/__init__.py
@@ -1,7 +1,7 @@
 # isort: skip_file
 """MS2PIP: Accurate and versatile peptide fragmentation spectrum prediction."""
 
-__version__ = "4.0.0-dev8"
+__version__ = "4.0.0-dev9"
 
 from warnings import filterwarnings