diff --git a/pyproject.toml b/pyproject.toml
index e43859e..05c8ade 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -5,7 +5,7 @@ build-backend = "hatchling.build"
 
 [project]
 name = "jsonata-python"
-version = "0.3.0"
+version = "0.4.0"
 description = "Pure Python implementation of JSONata"
 readme = "README.md"
 requires-python = ">=3.9"
diff --git a/src/jsonata/cli/__main__.py b/src/jsonata/cli/__main__.py
index 4f40864..ba6f65a 100644
--- a/src/jsonata/cli/__main__.py
+++ b/src/jsonata/cli/__main__.py
@@ -34,7 +34,7 @@ def get_options(argv: Optional[list[str]] = None) -> argparse.ArgumentParser:
     """
     parser = argparse.ArgumentParser(prog="jsonata.cli", description="Pure Python JSONata CLI")
     parser.add_argument(
-        "-v", "--version", action='version', version='%(prog)s 0.3.0')
+        "-v", "--version", action='version', version='%(prog)s 0.4.0')
 
     parser.add_argument(
         "-e", "--expression", metavar="<file>",