diff --git a/CHANGELOG.rst b/CHANGELOG.rst
index 3f6ca01..01179e0 100644
--- a/CHANGELOG.rst
+++ b/CHANGELOG.rst
@@ -1,6 +1,18 @@
 Release History
 ===============
 
+dev
+---
+
+**API Changes (Backward Incompatible)**
+
+-
+
+**Bugfixes**
+
+-
+
+
 4.0.0 (2020-08-30)
 ------------------
 
diff --git a/PKG-INFO b/PKG-INFO
index 9cd182c..92917c2 100644
--- a/PKG-INFO
+++ b/PKG-INFO
@@ -1,6 +1,6 @@
 Metadata-Version: 2.1
 Name: hpack
-Version: 4.0.0
+Version: 4.1.0+dev
 Summary: Pure-Python HPACK header compression
 Home-page: https://github.com/python-hyper/hpack
 Author: Cory Benfield
diff --git a/debian/changelog b/debian/changelog
index b43945e..ff0c6db 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -1,3 +1,6 @@
+python-hpack (4.0.0+git20200830.1.ce30f17-1) UNRELEASED; urgency=low
+ -- Debian Janitor <janitor@jelmer.uk>  Mon, 05 Apr 2021 06:13:43 -0000
+
 python-hpack (4.0.0-2) unstable; urgency=medium
 
   * Clean test/conftest.py since it’s broken anyway.
diff --git a/src/hpack.egg-info/PKG-INFO b/src/hpack.egg-info/PKG-INFO
index 9cd182c..92917c2 100644
--- a/src/hpack.egg-info/PKG-INFO
+++ b/src/hpack.egg-info/PKG-INFO
@@ -1,6 +1,6 @@
 Metadata-Version: 2.1
 Name: hpack
-Version: 4.0.0
+Version: 4.1.0+dev
 Summary: Pure-Python HPACK header compression
 Home-page: https://github.com/python-hyper/hpack
 Author: Cory Benfield
diff --git a/src/hpack/__init__.py b/src/hpack/__init__.py
index fc26ac5..8bede22 100644
--- a/src/hpack/__init__.py
+++ b/src/hpack/__init__.py
@@ -27,4 +27,4 @@ __all__ = [
     'InvalidTableSizeError',
 ]
 
-__version__ = '4.0.0'
+__version__ = '4.1.0+dev'