diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 7ec80fee..de6e82a1 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -35,12 +35,8 @@ jobs:
           - python: '3.11'
             os: macos-latest
           - python: '3.10'
-            os: ubuntu-latest
-          - python: '3.10'
-            os: macos-latest
-          - python: '3.9'
             os: windows-latest
-          - python: '3.9'
+          - python: '3.10'
             os: ubuntu-latest
             versions: minimal
     runs-on: ${{matrix.os}}
diff --git a/properdocs/commands/get_deps.py b/properdocs/commands/get_deps.py
index cf9f33d9..7b61b29d 100644
--- a/properdocs/commands/get_deps.py
+++ b/properdocs/commands/get_deps.py
@@ -8,7 +8,6 @@
 import io
 import logging
 import os
-import sys
 import urllib.parse
 from collections.abc import Collection, Mapping, Sequence
 from typing import IO, Any, BinaryIO
@@ -107,10 +106,7 @@ def _strings(obj) -> Sequence[str]:
 
 @functools.cache
 def _entry_points(group: str) -> Mapping[str, Any]:
-    if sys.version_info >= (3, 10):
-        from importlib.metadata import entry_points
-    else:
-        from importlib_metadata import entry_points
+    from importlib.metadata import entry_points
 
     eps = {ep.name: ep for ep in entry_points(group=group)}
     log.debug(f"Available '{group}' entry points: {sorted(eps)}")
diff --git a/properdocs/commands/serve.py b/properdocs/commands/serve.py
index afe3f847..cde09905 100644
--- a/properdocs/commands/serve.py
+++ b/properdocs/commands/serve.py
@@ -5,8 +5,9 @@
 import shutil
 import sys
 import tempfile
+from collections.abc import Callable
 from os.path import isdir, isfile, join
-from typing import TYPE_CHECKING, BinaryIO, Callable
+from typing import TYPE_CHECKING, BinaryIO
 from urllib.parse import urlsplit
 
 from properdocs.commands.build import build
diff --git a/properdocs/config/config_options.py b/properdocs/config/config_options.py
index 7a9a82a6..506e95d0 100644
--- a/properdocs/config/config_options.py
+++ b/properdocs/config/config_options.py
@@ -10,9 +10,9 @@
 import types
 import warnings
 from collections import Counter, UserString
-from collections.abc import Collection, Iterator, Mapping, MutableMapping
+from collections.abc import Callable, Collection, Iterator, Mapping, MutableMapping
 from types import SimpleNamespace
-from typing import Any, Callable, Generic, NamedTuple, TypeVar, Union, overload
+from typing import Any, Generic, NamedTuple, TypeVar, Union, overload
 from urllib.parse import quote as urlquote
 from urllib.parse import urlsplit, urlunsplit
 
diff --git a/properdocs/livereload/__init__.py b/properdocs/livereload/__init__.py
index f9e0a0b2..d742252e 100644
--- a/properdocs/livereload/__init__.py
+++ b/properdocs/livereload/__init__.py
@@ -21,8 +21,8 @@
 import webbrowser
 import wsgiref.simple_server
 import wsgiref.util
-from collections.abc import Iterable
-from typing import Any, BinaryIO, Callable
+from collections.abc import Callable, Iterable
+from typing import Any, BinaryIO
 
 import watchdog.events
 import watchdog.observers.polling
diff --git a/properdocs/plugins.py b/properdocs/plugins.py
index ff1b347f..78dcafb6 100644
--- a/properdocs/plugins.py
+++ b/properdocs/plugins.py
@@ -3,17 +3,12 @@
 from __future__ import annotations
 
 import logging
-import sys
-from collections.abc import MutableMapping
-from typing import TYPE_CHECKING, Any, Callable, Generic, Literal, TypeVar, overload
-
-if sys.version_info >= (3, 10):
-    from importlib.metadata import EntryPoint, entry_points
-else:
-    from importlib_metadata import EntryPoint, entry_points
+from collections.abc import Callable, MutableMapping
+from importlib.metadata import EntryPoint, entry_points
+from typing import TYPE_CHECKING, Any, Concatenate, Generic, Literal, TypeVar, overload
 
 if TYPE_CHECKING:
-    import jinja2.environment
+    import jinja2
 
 from properdocs import utils
 from properdocs.config.base import (
@@ -33,7 +28,7 @@
     from properdocs.utils.templates import TemplateContext
 
 if TYPE_CHECKING:
-    from typing_extensions import Concatenate, ParamSpec
+    from typing_extensions import ParamSpec
 else:
     ParamSpec = TypeVar
 
diff --git a/properdocs/structure/files.py b/properdocs/structure/files.py
index 67c372bc..c9277da3 100644
--- a/properdocs/structure/files.py
+++ b/properdocs/structure/files.py
@@ -7,10 +7,10 @@
 import posixpath
 import shutil
 import warnings
-from collections.abc import Iterable, Iterator, Mapping, Sequence
+from collections.abc import Callable, Iterable, Iterator, Mapping, Sequence
 from functools import cached_property
 from pathlib import PurePath, PurePosixPath
-from typing import TYPE_CHECKING, Callable, overload
+from typing import TYPE_CHECKING, overload
 from urllib.parse import quote as urlquote
 
 import pathspec
diff --git a/properdocs/structure/pages.py b/properdocs/structure/pages.py
index b03bacfb..8c58e24f 100644
--- a/properdocs/structure/pages.py
+++ b/properdocs/structure/pages.py
@@ -4,8 +4,8 @@
 import logging
 import posixpath
 import warnings
-from collections.abc import Iterator, MutableMapping, Sequence
-from typing import TYPE_CHECKING, Any, Callable
+from collections.abc import Callable, Iterator, MutableMapping, Sequence
+from typing import TYPE_CHECKING, Any
 from urllib.parse import unquote as urlunquote
 from urllib.parse import urljoin, urlsplit, urlunsplit
 
diff --git a/properdocs/tests/structure/file_tests.py b/properdocs/tests/structure/file_tests.py
index 3efc7b3a..744d09ae 100644
--- a/properdocs/tests/structure/file_tests.py
+++ b/properdocs/tests/structure/file_tests.py
@@ -1,3 +1,4 @@
+import itertools
 import os
 import sys
 import unittest
@@ -64,7 +65,7 @@ def test_file_sort_key(self):
         ]:
             with self.subTest(case):
                 files = [File(f, "", "", use_directory_urls=True) for f in case]
-                for a, b in zip(files, files[1:]):
+                for a, b in itertools.pairwise(files):
                     self.assertLess(file_sort_key(a), file_sort_key(b))
 
     def test_md_file(self):
diff --git a/properdocs/tests/structure/page_tests.py b/properdocs/tests/structure/page_tests.py
index 6ef13404..8c9d1026 100644
--- a/properdocs/tests/structure/page_tests.py
+++ b/properdocs/tests/structure/page_tests.py
@@ -785,11 +785,9 @@ def get_rendered_result(
                 pg.render(cfg, Files(fs))
             msgs = [f'{r.levelname}:{r.message}' for r in cm.records]
             self.assertEqual('\n'.join(msgs), textwrap.dedent(logs).strip('\n'))
-        elif sys.version_info >= (3, 10):
+        else:
             with self.assertNoLogs('properdocs.structure.pages'):
                 pg.render(cfg, Files(fs))
-        else:
-            pg.render(cfg, Files(fs))
 
         assert pg.content is not None
         content = pg.content
diff --git a/properdocs/utils/__init__.py b/properdocs/utils/__init__.py
index 2cc6813c..a901548c 100644
--- a/properdocs/utils/__init__.py
+++ b/properdocs/utils/__init__.py
@@ -13,20 +13,16 @@
 import posixpath
 import re
 import shutil
-import sys
 import warnings
+from bisect import insort  # noqa: F401 - legacy re-export
 from collections import defaultdict
-from collections.abc import Collection, Iterable, MutableSequence
+from collections.abc import Collection, Iterable
 from datetime import datetime, timezone
+from importlib.metadata import EntryPoint, entry_points
 from pathlib import PurePath
 from typing import TYPE_CHECKING, TypeVar
 from urllib.parse import urlsplit
 
-if sys.version_info >= (3, 10):
-    from importlib.metadata import EntryPoint, entry_points
-else:
-    from importlib_metadata import EntryPoint, entry_points
-
 from properdocs import exceptions
 from properdocs.utils.yaml import get_yaml_loader, yaml_load  # noqa: F401 - legacy re-export
 
@@ -93,18 +89,6 @@ def reduce_list(data_set: Iterable[T]) -> list[T]:
     return list(dict.fromkeys(data_set))
 
 
-if sys.version_info >= (3, 10):
-    from bisect import insort
-else:
-
-    def insort(a: MutableSequence[T], x: T, *, key=lambda v: v) -> None:
-        kx = key(x)
-        i = len(a)
-        while i > 0 and kx < key(a[i - 1]):
-            i -= 1
-        a.insert(i, x)
-
-
 def copy_file(source_path: str, output_path: str) -> None:
     """
     Copy source_path to output_path, making sure any parent directories exist.
diff --git a/properdocs/utils/cache.py b/properdocs/utils/cache.py
index 070df169..8dc87f08 100644
--- a/properdocs/utils/cache.py
+++ b/properdocs/utils/cache.py
@@ -8,7 +8,7 @@
 import os
 import random
 import urllib.request
-from typing import Callable
+from collections.abc import Callable
 
 import platformdirs
 
diff --git a/properdocs/utils/rendering.py b/properdocs/utils/rendering.py
index 545e1efb..0f1a3d7a 100644
--- a/properdocs/utils/rendering.py
+++ b/properdocs/utils/rendering.py
@@ -1,7 +1,8 @@
 from __future__ import annotations
 
 import copy
-from typing import TYPE_CHECKING, Callable
+from collections.abc import Callable
+from typing import TYPE_CHECKING
 
 import markdown
 import markdown.treeprocessors
diff --git a/pyproject.toml b/pyproject.toml
index ebc97d70..779faffc 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -20,7 +20,6 @@ classifiers = [
     "Programming Language :: Python",
     # Begin Python versions
     "Programming Language :: Python :: 3",
-    "Programming Language :: Python :: 3.9",
     "Programming Language :: Python :: 3.10",
     "Programming Language :: Python :: 3.11",
     "Programming Language :: Python :: 3.12",
@@ -32,7 +31,7 @@ classifiers = [
     "Typing :: Typed",
 ]
 dynamic = ["version"]
-requires-python = ">=3.9"
+requires-python = ">=3.10"
 dependencies = [
     "click >=7.0",
     "Jinja2 >=2.11.1",
@@ -106,7 +105,7 @@ _coverage = [
 ]
 with-coverage = "test"
 [[tool.hatch.envs.test.matrix]]
-python = ["3.9", "3.10", "3.11", "3.12", "3.13", "3.14"]
+python = ["3.10", "3.11", "3.12", "3.13", "3.14"]
 [tool.hatch.envs.test.overrides]
 matrix.type.scripts = [
     { key = "with-coverage", value = "_coverage", if = ["default"] },
@@ -120,7 +119,7 @@ template = "test"
 [tool.hatch.envs.integration.scripts]
 test = "python -m properdocs.tests.integration"
 [[tool.hatch.envs.integration.matrix]]
-python = ["3.9", "3.10", "3.11", "3.12", "3.13", "3.14"]
+python = ["3.10", "3.11", "3.12", "3.13", "3.14"]
 type = ["default", "no-babel"]
 [tool.hatch.envs.integration.overrides]
 matrix.type.features = [