diff --git a/optimed/__init__.py b/optimed/__init__.py
index 7ad723c..e8fc95e 100644
--- a/optimed/__init__.py
+++ b/optimed/__init__.py
@@ -1,4 +1,4 @@
-__version__ = "1.0.0"
+__version__ = "1.0.0a0"
 
 
 def _check_availability(name: str) -> bool:
diff --git a/pyproject.toml b/pyproject.toml
index 3b07b8c..f7ff5df 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -4,7 +4,7 @@ build-backend = "setuptools.build_meta"
 
 [project]
 name = "optimed"
-version = "1.0.0-preview"
+version = "1.0.0a0"
 description = "Optimed"
 readme = "README.md"
 license = { text = "Apache-2.0" }