diff --git a/codegraph/__init__.py b/codegraph/__init__.py
index 361322f..ad3beb2 100644
--- a/codegraph/__init__.py
+++ b/codegraph/__init__.py
@@ -1,3 +1,11 @@
 """codegraph, Local code graph index for AI coding assistants."""
 
-__version__ = "0.4.6"
+from importlib.metadata import PackageNotFoundError, version
+
+try:
+    # Single source of truth: the installed package version (pyproject.toml).
+    # Avoids the banner drifting from the real version on a release bump.
+    __version__ = version("cgh")
+except PackageNotFoundError:
+    # Running from a source tree with no installed metadata.
+    __version__ = "0.0.0+source"