diff --git a/nifty4/version.py b/nifty4/version.py
index 3b92dc0a016d5cd37528bea2233f64676d56c7ee..7151bb7b277eacc7489713bb2ec70b10ac9114db 100644
--- a/nifty4/version.py
+++ b/nifty4/version.py
@@ -3,7 +3,8 @@
 # 2) we can import it in setup.py for the same reason
 # 3) we can import it into your module module
 
-__version__ = '3.9.0'
+__version__ = '4.0.0'
+
 
 def gitversion():
     try:
diff --git a/setup.py b/setup.py
index 743c7c1b62e3cb3f63f0af7d1a77f78501fcde01..7d1781038d17f4ae4559e82c737c878daa8c6de5 100644
--- a/setup.py
+++ b/setup.py
@@ -18,6 +18,7 @@
 
 from setuptools import setup, find_packages
 
+
 def write_version():
     import subprocess
     p = subprocess.Popen(["git", "describe", "--dirty"],
@@ -26,6 +27,7 @@ def write_version():
     with open("nifty4/git_version.py", "w") as file:
         file.write('gitversion = "{}"\n'.format(res))
 
+
 write_version()
 exec(open('nifty4/version.py').read())