diff --git a/CHANGES.md b/CHANGES.md
index 29d82dc..aef44d8 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -2,6 +2,9 @@
 
 ## 2023
 
+#### v0.8.5 (TBD)
+
+
 #### v0.8.4 (2023-10-18)
 
 Performance:
diff --git a/pyproject.toml b/pyproject.toml
index 7357aeb..c226b0e 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,6 +1,6 @@
 [project]
 name='CyRK'
-version = '0.8.4'
+version = '0.8.5a0.dev1'
 description='Runge-Kutta ODE Integrator Implemented in Cython and Numba.'
 authors= [
     {name = 'Joe P. Renaud', email = 'joe.p.renaud@gmail.com'}