diff --git a/pyproject.toml b/pyproject.toml
index d9cb32c..cf4dda2 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "sphinx-revealjs"
-version = "0.12.1"
+version = "1.0.0.b1"
 description = "Sphinx extension with theme to generate Reveal.js presentation"
 authors = ["Kazuya Takei <myself@attakei.net>"]
 classifiers = [
diff --git a/setup.cfg b/setup.cfg
index c234027..2a82a5e 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -1,5 +1,5 @@
 [bumpversion]
-current_version = 0.12.1
+current_version = 1.0.0.b1
 commit = False
 tag = False
 
diff --git a/sphinx_revealjs/__init__.py b/sphinx_revealjs/__init__.py
index 1d1c359..5333e08 100644
--- a/sphinx_revealjs/__init__.py
+++ b/sphinx_revealjs/__init__.py
@@ -1,6 +1,6 @@
 """Root module for sphinx-revealjs."""
 
-__version__ = "0.12.1"
+__version__ = "1.0.0.b1"
 
 
 from sphinx.application import Sphinx