diff --git a/README.rst b/README.rst
index 6dc1e27..b7ddbbb 100644
--- a/README.rst
+++ b/README.rst
@@ -383,7 +383,7 @@ Once you have `pre-commit`_ installed, add the follwong to the
 
     repos:
     - repo: https://github.com/kynan/nbstripout
-      rev: 0.3.9
+      rev: 0.4.0
       hooks:
         - id: nbstripout
 
diff --git a/nbstripout/_nbstripout.py b/nbstripout/_nbstripout.py
index 1c6a723..aa5acae 100644
--- a/nbstripout/_nbstripout.py
+++ b/nbstripout/_nbstripout.py
@@ -139,7 +139,7 @@ def write(nb, f):
             return current.write(nb, f, 'json')
 
 __all__ = ["install", "uninstall", "status", "main"]
-__version__ = '0.3.9'
+__version__ = '0.4.0'
 
 
 INSTALL_LOCATION_LOCAL = 'local'
diff --git a/setup.cfg b/setup.cfg
index f644309..8a1de58 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -1,5 +1,5 @@
 [bumpversion]
-current_version = 0.3.9
+current_version = 0.4.0
 commit = True
 tag = True
 tag_name = {new_version}
diff --git a/setup.py b/setup.py
index 79e1a87..a848193 100644
--- a/setup.py
+++ b/setup.py
@@ -19,7 +19,7 @@
 ]
 
 setup(name='nbstripout',
-      version='0.3.9',
+      version='0.4.0',
 
       author='Florian Rathgeber',
       author_email='florian.rathgeber@gmail.com',