diff --git a/README.md b/README.md
index cf6b72d..18f42f9 100644
--- a/README.md
+++ b/README.md
@@ -2,7 +2,7 @@
 
 <a href="https://opensource.org"><img height="150" align="left" src="https://opensource.org/files/OSIApprovedCropped.png" alt="Open Source Initiative Approved License logo"></a>
 [![CI](https://github.com/kpfleming/jinjanator-plugin-format-xml/actions/workflows/ci.yml/badge.svg?branch=main)](https://github.com/kpfleming/jinjanator-plugin-format-xml/actions/workflows/ci.yml)
-[![Python](https://img.shields.io/badge/python-3.9+-blue.svg)](https://www.python.org/downloads/release/python-3920/)
+[![Python](https://img.shields.io/badge/python-3.10+-blue.svg)](https://www.python.org/downloads/release/python-31019/)
 [![License - Apache 2.0](https://img.shields.io/badge/License-Apache%202.0-9400d3.svg)](https://spdx.org/licenses/Apache-2.0.html)
 [![Code Style - Black](https://img.shields.io/badge/Code%20Style-Black-000000.svg)](https://github.com/psf/black)
 [![Types - Mypy](https://img.shields.io/badge/Types-Mypy-blue.svg)](https://github.com/python/mypy)
diff --git a/changelog.d/+87dcfdc6.breaking.md b/changelog.d/+87dcfdc6.breaking.md
new file mode 100644
index 0000000..896fdd3
--- /dev/null
+++ b/changelog.d/+87dcfdc6.breaking.md
@@ -0,0 +1,3 @@
+Support for Python 3.9 has been removed, and support for Python 3.14
+has been added. Since the minimum supported version is now 3.10, the
+code has been updated to use features introduced in that version.
diff --git a/pyproject.toml b/pyproject.toml
index 6a26040..98583a1 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -13,7 +13,7 @@ license = { text = "Apache-2.0" }
 authors = [
   { name = "Kevin P. Fleming", email = "jinjanator@kevin.km6g.us" },
 ]
-requires-python = ">=3.9"
+requires-python = ">=3.10"
 classifiers = [
   "Development Status :: 5 - Production/Stable",
   "Environment :: Console",
@@ -22,11 +22,11 @@ classifiers = [
   "Natural Language :: English",
   "Operating System :: OS Independent",
   "Programming Language :: Python :: 3 :: Only",
-  "Programming Language :: Python :: 3.9",
   "Programming Language :: Python :: 3.10",
   "Programming Language :: Python :: 3.11",
   "Programming Language :: Python :: 3.12",
   "Programming Language :: Python :: 3.13",
+  "Programming Language :: Python :: 3.14",
   "Typing :: Typed",
 ]
 dynamic = [
@@ -209,6 +209,9 @@ lint.unfixable = [
 lint.isort.lines-after-imports = 2
 lint.isort.lines-between-types = 1
 
+[tool.pyproject-fmt]
+max_supported_python = "3.14"
+
 [tool.pytest.ini_options]
 minversion = "6.0"
 xfail_strict = true
@@ -264,7 +267,7 @@ name = "Fixes"
 showcontent = true
 
 [tool.mypy]
-python_version = 3.9
+python_version = "3.10"
 namespace_packages = true
 explicit_package_bases = true
 check_untyped_defs = true
diff --git a/src/jinjanator_plugin_format_xml/plugin.py b/src/jinjanator_plugin_format_xml/plugin.py
index ed0ab41..45aefe0 100644
--- a/src/jinjanator_plugin_format_xml/plugin.py
+++ b/src/jinjanator_plugin_format_xml/plugin.py
@@ -1,5 +1,5 @@
 from collections.abc import Iterable, Mapping
-from typing import Any, Optional
+from typing import Any
 
 import xmltodict
 
@@ -11,10 +11,10 @@
 
 class XMLFormat:
     name = "xml"
-    suffixes: Optional[Iterable[str]] = ".xml"
-    option_names: Optional[Iterable[str]] = "process-namespaces"
+    suffixes: Iterable[str] | None = ".xml"
+    option_names: Iterable[str] | None = "process-namespaces"
 
-    def __init__(self, options: Optional[Iterable[str]]) -> None:
+    def __init__(self, options: Iterable[str] | None) -> None:
         self.process_namespaces = False
         if options:
             for _option in options:
diff --git a/workflow-support/versions.json b/workflow-support/versions.json
index 6f1e258..582a602 100644
--- a/workflow-support/versions.json
+++ b/workflow-support/versions.json
@@ -1 +1 @@
-versions={"python": ["3.9", "3.10", "3.11", "3.12", "3.13", "3.14"]}
+versions={"python": ["3.10", "3.11", "3.12", "3.13", "3.14"]}