diff --git a/bindings/python/notmuch/version.py b/bindings/python/notmuch/version.py
index fbb282e3..110b75d4 100644
--- a/bindings/python/notmuch/version.py
+++ b/bindings/python/notmuch/version.py
@@ -1,3 +1,3 @@
 # this file should be kept in sync with ../../../version
-__VERSION__ = '0.27'
+__VERSION__ = '0.28~rc0'
 SOVERSION = '5'
diff --git a/version b/version
index 5a9e6bda..03829429 100644
--- a/version
+++ b/version
@@ -1 +1 @@
-0.27
+0.28~rc0