diff --git a/VERSION b/VERSION
index 52356d37..fb16a995 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-1.3.50
+1.3.51-dev0
diff --git a/setup.cfg b/setup.cfg
index 9e504a1b..46a28439 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -1,5 +1,5 @@
 [bumpversion]
-current_version = 1.3.50
+current_version = 1.3.51-dev0
 commit = True
 tag = False
 parse = (?P<major>\d+)\.(?P<minor>\d+)\.(?P<patch>\d+)(\-(?P<release>[a-z]+)(?P<build>\d+))?
diff --git a/setup.py b/setup.py
index 7837f128..8600c135 100644
--- a/setup.py
+++ b/setup.py
@@ -6,7 +6,7 @@
     setup_requires.append('pytest-runner')
 
 setup(name='nb2workflow',
-      version = '1.3.50',
+      version = '1.3.51-dev0',
       description='convert notebook to workflow',
       author='Volodymyr Savchenko',
       author_email='contact@volodymyrsavchenko.com',