diff --git a/PyHEADTAIL/_version.py b/PyHEADTAIL/_version.py
index f54fa443..4d6a9dcb 100644
--- a/PyHEADTAIL/_version.py
+++ b/PyHEADTAIL/_version.py
@@ -1 +1 @@
-__version__ = '1.13.3'
+__version__ = '1.13.4'
diff --git a/setup.py b/setup.py
index 4c53e8a6..34173101 100755
--- a/setup.py
+++ b/setup.py
@@ -6,8 +6,7 @@
 import numpy as np
 from PyHEADTAIL._version import __version__
 
-import re, os, sys, subprocess
-import numpy as np
+import os, sys, subprocess
 
 from setuptools import setup, Extension, find_packages
 
@@ -55,7 +54,10 @@
 # Set up extension and build
 cy_ext_options = {
     "compiler_directives": {"profile": False, # SLOW!!!
-                            "embedsignature": True},
+                            "embedsignature": True,
+                            "linetrace": False,
+                            "language_level": sys.version_info[0],
+                            },
     "annotate": True,
 }
 cy_ext = [