diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
new file mode 100644
index 0000000..6c895f2
--- /dev/null
+++ b/.github/workflows/tests.yml
@@ -0,0 +1,31 @@
+name: Tests
+
+on:
+  push:
+    branches: [main]
+  pull_request:
+    branches: [main]
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        python-version: ["3.10", "3.11", "3.12", "3.13", "3.14"]
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Set up Python ${{ matrix.python-version }}
+        uses: actions/setup-python@v5
+        with:
+          python-version: ${{ matrix.python-version }}
+
+      - name: Install package
+        run: |
+          python -m pip install --upgrade pip
+          pip install -e .
+
+      - name: Run tests
+        run: python -m unittest discover -s tests -v
diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index 9a809f7..cbd1ce4 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -19,7 +19,7 @@ repos:
     rev: v3.21.2
     hooks:
       - id: pyupgrade
-        args: ['--py36-plus']
+        args: ['--py310-plus']
   - repo: https://github.com/pycqa/flake8
     rev: 7.3.0
     hooks:
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
new file mode 100644
index 0000000..458486c
--- /dev/null
+++ b/CONTRIBUTING.md
@@ -0,0 +1,41 @@
+# Contributing
+
+Thanks for considering a contribution!
+
+## Setup
+
+```sh
+python3 -m venv .venv
+.venv/bin/pip install -e .
+.venv/bin/pip install pre-commit
+.venv/bin/pre-commit install
+```
+
+## Running tests
+
+```sh
+.venv/bin/python -m unittest discover -vs tests
+```
+
+Tests also run in CI on Python 3.10–3.14. New hooks should ship with tests
+in `tests/`.
+
+## Linting and formatting
+
+`pre-commit` runs `black`, `isort`, `flake8`, and `pyupgrade`. Either let
+the installed hook handle it on commit, or run it manually:
+
+```sh
+.venv/bin/pre-commit run --all-files
+```
+
+pre-commit.ci also runs these hooks on every PR.
+
+## Adding a new hook
+
+A new hook needs:
+
+- An entry in `.pre-commit-hooks.yaml`
+- An entry point in `setup.py`
+- A usage example in `README.md`
+- Tests in `tests/`
diff --git a/pre_commit_macadmin_hooks/check_autopkg_recipe_list.py b/pre_commit_macadmin_hooks/check_autopkg_recipe_list.py
index bcc5217..33dac68 100755
--- a/pre_commit_macadmin_hooks/check_autopkg_recipe_list.py
+++ b/pre_commit_macadmin_hooks/check_autopkg_recipe_list.py
@@ -8,7 +8,6 @@
 import argparse
 import json
 import plistlib
-from typing import List, Optional
 from xml.parsers.expat import ExpatError
 
 import ruamel.yaml
@@ -26,7 +25,7 @@ def build_argument_parser() -> argparse.ArgumentParser:
     return parser
 
 
-def main(argv: Optional[List[str]] = None) -> int:
+def main(argv: list[str] | None = None) -> int:
     """Main process."""
 
     # Parse command line arguments.
diff --git a/pre_commit_macadmin_hooks/check_autopkg_recipes.py b/pre_commit_macadmin_hooks/check_autopkg_recipes.py
index 89dc51d..6b1c891 100755
--- a/pre_commit_macadmin_hooks/check_autopkg_recipes.py
+++ b/pre_commit_macadmin_hooks/check_autopkg_recipes.py
@@ -6,7 +6,7 @@
 import os
 import sys
 from contextlib import contextmanager
-from typing import Any, Dict, List
+from typing import Any
 
 from packaging.version import Version
 
@@ -88,7 +88,7 @@ def build_argument_parser() -> argparse.ArgumentParser:
 
 
 def validate_recipe_prefix(
-    recipe: Dict[str, Any], filename: str, prefix: List[str]
+    recipe: dict[str, Any], filename: str, prefix: list[str]
 ) -> bool:
     """Verify that the recipe identifier starts with the expected prefix."""
 
diff --git a/pre_commit_macadmin_hooks/check_git_config_email.py b/pre_commit_macadmin_hooks/check_git_config_email.py
index fd55a26..2339332 100644
--- a/pre_commit_macadmin_hooks/check_git_config_email.py
+++ b/pre_commit_macadmin_hooks/check_git_config_email.py
@@ -3,7 +3,6 @@
 
 import argparse
 import subprocess
-from typing import List, Optional
 
 
 def build_argument_parser() -> argparse.ArgumentParser:
@@ -20,7 +19,7 @@ def build_argument_parser() -> argparse.ArgumentParser:
     return parser
 
 
-def main(argv: Optional[List[str]] = None) -> int:
+def main(argv: list[str] | None = None) -> int:
     """Main process."""
 
     # Parse command line arguments.
diff --git a/pre_commit_macadmin_hooks/check_jamf_extension_attributes.py b/pre_commit_macadmin_hooks/check_jamf_extension_attributes.py
index 112577d..bd38d04 100644
--- a/pre_commit_macadmin_hooks/check_jamf_extension_attributes.py
+++ b/pre_commit_macadmin_hooks/check_jamf_extension_attributes.py
@@ -3,7 +3,6 @@
 
 import argparse
 import re
-from typing import List, Optional
 
 from pre_commit_macadmin_hooks.util import validate_shebangs
 
@@ -24,7 +23,7 @@ def build_argument_parser() -> argparse.ArgumentParser:
     return parser
 
 
-def main(argv: Optional[List[str]] = None) -> int:
+def main(argv: list[str] | None = None) -> int:
     """Main process."""
 
     # Parse command line arguments.
diff --git a/pre_commit_macadmin_hooks/check_jamf_json_manifests.py b/pre_commit_macadmin_hooks/check_jamf_json_manifests.py
index 8f346a9..4face82 100755
--- a/pre_commit_macadmin_hooks/check_jamf_json_manifests.py
+++ b/pre_commit_macadmin_hooks/check_jamf_json_manifests.py
@@ -8,7 +8,7 @@
 import argparse
 import json
 from datetime import datetime
-from typing import Any, Dict, List, Optional, Tuple
+from typing import Any
 
 from pre_commit_macadmin_hooks.util import validate_required_keys
 
@@ -45,7 +45,7 @@ def build_argument_parser() -> argparse.ArgumentParser:
     return parser
 
 
-def validate_key_types(name: str, manifest: Dict[str, Any], filename: str) -> bool:
+def validate_key_types(name: str, manifest: dict[str, Any], filename: str) -> bool:
     """Validation of manifest key types."""
 
     # Manifest keys and their known types. Omitted keys are left unvalidated.
@@ -80,8 +80,8 @@ def validate_key_types(name: str, manifest: Dict[str, Any], filename: str) -> bo
 
 
 def validate_type(
-    name: str, property: Dict[str, Any], filename: str
-) -> Tuple[bool, Optional[str]]:  # noqa: A002
+    name: str, property: dict[str, Any], filename: str
+) -> tuple[bool, str | None]:  # noqa: A002
     """Ensure property type keu is present and among expected values."""
     passed = True
     type_found = None
@@ -102,7 +102,7 @@ def validate_type(
 
 
 def validate_list_item_types(
-    name: str, manifest: Dict[str, Any], filename: str
+    name: str, manifest: dict[str, Any], filename: str
 ) -> bool:
     """Validation of list member items."""
 
@@ -131,7 +131,7 @@ def validate_list_item_types(
 
 
 def validate_default(
-    name: str, prop: Dict[str, Any], type_found: Optional[str], filename: str
+    name: str, prop: dict[str, Any], type_found: str | None, filename: str
 ) -> bool:
     """Ensure that default values have the expected type."""
     passed = True
@@ -151,7 +151,7 @@ def validate_default(
     return passed
 
 
-def validate_urls(name: str, prop: Dict[str, Any], filename: str) -> bool:
+def validate_urls(name: str, prop: dict[str, Any], filename: str) -> bool:
     """Ensure that URL values are actual URLs."""
     passed = True
 
@@ -167,7 +167,7 @@ def validate_urls(name: str, prop: Dict[str, Any], filename: str) -> bool:
     return passed
 
 
-def validate_properties(properties: Dict[str, Any], filename: str) -> bool:
+def validate_properties(properties: dict[str, Any], filename: str) -> bool:
     """Given a list of properties, run validation on their contents."""
     passed = True
 
@@ -206,7 +206,7 @@ def validate_properties(properties: Dict[str, Any], filename: str) -> bool:
     return passed
 
 
-def main(argv: Optional[List[str]] = None) -> int:
+def main(argv: list[str] | None = None) -> int:
     """Main process."""
 
     # Parse command line arguments.
diff --git a/pre_commit_macadmin_hooks/check_jamf_profiles.py b/pre_commit_macadmin_hooks/check_jamf_profiles.py
index 692fdb1..c03e03d 100644
--- a/pre_commit_macadmin_hooks/check_jamf_profiles.py
+++ b/pre_commit_macadmin_hooks/check_jamf_profiles.py
@@ -3,7 +3,6 @@
 
 import argparse
 import plistlib
-from typing import List, Optional
 from xml.parsers.expat import ExpatError
 
 
@@ -17,7 +16,7 @@ def build_argument_parser() -> argparse.ArgumentParser:
     return parser
 
 
-def main(argv: Optional[List[str]] = None) -> int:
+def main(argv: list[str] | None = None) -> int:
     """Main process."""
 
     # Parse command line arguments.
diff --git a/pre_commit_macadmin_hooks/check_jamf_scripts.py b/pre_commit_macadmin_hooks/check_jamf_scripts.py
index e08c4b2..5c3c18d 100644
--- a/pre_commit_macadmin_hooks/check_jamf_scripts.py
+++ b/pre_commit_macadmin_hooks/check_jamf_scripts.py
@@ -2,7 +2,6 @@
 """Check Jamf scripts for common issues."""
 
 import argparse
-from typing import List, Optional
 
 from pre_commit_macadmin_hooks.util import validate_shebangs
 
@@ -23,7 +22,7 @@ def build_argument_parser() -> argparse.ArgumentParser:
     return parser
 
 
-def main(argv: Optional[List[str]] = None) -> int:
+def main(argv: list[str] | None = None) -> int:
     """Main process."""
 
     # Parse command line arguments.
diff --git a/pre_commit_macadmin_hooks/check_munki_pkgsinfo.py b/pre_commit_macadmin_hooks/check_munki_pkgsinfo.py
index aaa1a22..b1989d8 100755
--- a/pre_commit_macadmin_hooks/check_munki_pkgsinfo.py
+++ b/pre_commit_macadmin_hooks/check_munki_pkgsinfo.py
@@ -5,7 +5,6 @@
 import os
 import plistlib
 from pathlib import Path
-from typing import List, Optional
 from xml.parsers.expat import ExpatError
 
 from pre_commit_macadmin_hooks.util import (
@@ -89,7 +88,7 @@ def _check_case_sensitive_path(path: str) -> bool:
         p = p.parent
 
 
-def main(argv: Optional[List[str]] = None) -> int:
+def main(argv: list[str] | None = None) -> int:
     """Main process."""
 
     # Typical extensions for installer packages.
diff --git a/pre_commit_macadmin_hooks/check_munkiadmin_scripts.py b/pre_commit_macadmin_hooks/check_munkiadmin_scripts.py
index 988529e..a730dc0 100755
--- a/pre_commit_macadmin_hooks/check_munkiadmin_scripts.py
+++ b/pre_commit_macadmin_hooks/check_munkiadmin_scripts.py
@@ -3,7 +3,6 @@
 
 import argparse
 import os
-from typing import List, Optional
 
 from pre_commit_macadmin_hooks.util import validate_shebangs
 
@@ -24,7 +23,7 @@ def build_argument_parser() -> argparse.ArgumentParser:
     return parser
 
 
-def main(argv: Optional[List[str]] = None) -> int:
+def main(argv: list[str] | None = None) -> int:
     """Main process."""
 
     # Parse command line arguments.
diff --git a/pre_commit_macadmin_hooks/check_munkipkg_buildinfo.py b/pre_commit_macadmin_hooks/check_munkipkg_buildinfo.py
index 1c0dfb8..118271c 100755
--- a/pre_commit_macadmin_hooks/check_munkipkg_buildinfo.py
+++ b/pre_commit_macadmin_hooks/check_munkipkg_buildinfo.py
@@ -4,7 +4,7 @@
 import argparse
 import json
 import plistlib
-from typing import Any, Dict, List, Optional
+from typing import Any
 from xml.parsers.expat import ExpatError
 
 import ruamel.yaml
@@ -29,7 +29,7 @@ def build_argument_parser() -> argparse.ArgumentParser:
     return parser
 
 
-def validate_buildinfo_key_types(buildinfo: Dict[str, Any], filename: str) -> bool:
+def validate_buildinfo_key_types(buildinfo: dict[str, Any], filename: str) -> bool:
     """Ensure build-info files contain the proper types."""
 
     # Pkginfo keys and their known types. Omitted keys are left unvalidated.
@@ -62,7 +62,7 @@ def validate_buildinfo_key_types(buildinfo: Dict[str, Any], filename: str) -> bo
     return passed
 
 
-def main(argv: Optional[List[str]] = None) -> int:
+def main(argv: list[str] | None = None) -> int:
     """Main process."""
 
     # Parse command line arguments.
diff --git a/pre_commit_macadmin_hooks/check_outset_scripts.py b/pre_commit_macadmin_hooks/check_outset_scripts.py
index 074cf10..d945971 100644
--- a/pre_commit_macadmin_hooks/check_outset_scripts.py
+++ b/pre_commit_macadmin_hooks/check_outset_scripts.py
@@ -3,7 +3,6 @@
 
 import argparse
 import os
-from typing import List, Optional
 
 from pre_commit_macadmin_hooks.util import validate_shebangs
 
@@ -24,7 +23,7 @@ def build_argument_parser() -> argparse.ArgumentParser:
     return parser
 
 
-def main(argv: Optional[List[str]] = None) -> int:
+def main(argv: list[str] | None = None) -> int:
     """Main process."""
 
     # Parse command line arguments.
diff --git a/pre_commit_macadmin_hooks/check_plists.py b/pre_commit_macadmin_hooks/check_plists.py
index 363332e..eb75578 100755
--- a/pre_commit_macadmin_hooks/check_plists.py
+++ b/pre_commit_macadmin_hooks/check_plists.py
@@ -3,7 +3,6 @@
 
 import argparse
 import plistlib
-from typing import List, Optional
 from xml.parsers.expat import ExpatError
 
 
@@ -17,7 +16,7 @@ def build_argument_parser() -> argparse.ArgumentParser:
     return parser
 
 
-def main(argv: Optional[List[str]] = None) -> int:
+def main(argv: list[str] | None = None) -> int:
     """Main process."""
 
     # Parse command line arguments.
diff --git a/pre_commit_macadmin_hooks/check_preference_manifests.py b/pre_commit_macadmin_hooks/check_preference_manifests.py
index 4bf72a2..aca9768 100755
--- a/pre_commit_macadmin_hooks/check_preference_manifests.py
+++ b/pre_commit_macadmin_hooks/check_preference_manifests.py
@@ -9,7 +9,7 @@
 import argparse
 import plistlib
 from datetime import datetime
-from typing import Any, Dict, List, Optional, Tuple
+from typing import Any
 from xml.parsers.expat import ExpatError
 
 from pre_commit_macadmin_hooks.util import PLIST_TYPES
@@ -40,8 +40,8 @@ def build_argument_parser() -> argparse.ArgumentParser:
 
 
 def validate_required_keys(
-    input_dict: Dict[str, Any],
-    required_keys: Tuple[str, ...],
+    input_dict: dict[str, Any],
+    required_keys: tuple[str, ...],
     dict_name: str,
     filename: str,
 ) -> bool:
@@ -54,7 +54,7 @@ def validate_required_keys(
     return passed
 
 
-def validate_manifest_key_types(manifest: Dict[str, Any], filename: str) -> bool:
+def validate_manifest_key_types(manifest: dict[str, Any], filename: str) -> bool:
     """Validation of manifest key types."""
 
     # manifest keys and their known types. Omitted keys are left un-validated.
@@ -410,7 +410,7 @@ def validate_subkeys(subkeys, filename):
     return passed
 
 
-def main(argv: Optional[List[str]] = None) -> int:
+def main(argv: list[str] | None = None) -> int:
     """Main process."""
 
     # Parse command line arguments.
diff --git a/pre_commit_macadmin_hooks/forbid_autopkg_overrides.py b/pre_commit_macadmin_hooks/forbid_autopkg_overrides.py
index 3f85856..1ad6bc4 100755
--- a/pre_commit_macadmin_hooks/forbid_autopkg_overrides.py
+++ b/pre_commit_macadmin_hooks/forbid_autopkg_overrides.py
@@ -2,7 +2,6 @@
 """This hook prevents AutoPkg overrides from being added to the repo."""
 
 import argparse
-from typing import List, Optional
 
 from pre_commit_macadmin_hooks.util import load_autopkg_recipe
 
@@ -17,7 +16,7 @@ def build_argument_parser() -> argparse.ArgumentParser:
     return parser
 
 
-def main(argv: Optional[List[str]] = None) -> int:
+def main(argv: list[str] | None = None) -> int:
     """Main process."""
 
     # Overrides should not contain top-level Process arrays.
diff --git a/pre_commit_macadmin_hooks/forbid_autopkg_trust_info.py b/pre_commit_macadmin_hooks/forbid_autopkg_trust_info.py
index 1333b5e..8e67e86 100644
--- a/pre_commit_macadmin_hooks/forbid_autopkg_trust_info.py
+++ b/pre_commit_macadmin_hooks/forbid_autopkg_trust_info.py
@@ -3,7 +3,6 @@
 repo."""
 
 import argparse
-from typing import List, Optional
 
 from pre_commit_macadmin_hooks.util import load_autopkg_recipe
 
@@ -18,7 +17,7 @@ def build_argument_parser() -> argparse.ArgumentParser:
     return parser
 
 
-def main(argv: Optional[List[str]] = None) -> int:
+def main(argv: list[str] | None = None) -> int:
     """Main process."""
 
     # Parse command line arguments.
diff --git a/pre_commit_macadmin_hooks/format_autopkg_yaml_recipes.py b/pre_commit_macadmin_hooks/format_autopkg_yaml_recipes.py
index b93f232..0b931f0 100644
--- a/pre_commit_macadmin_hooks/format_autopkg_yaml_recipes.py
+++ b/pre_commit_macadmin_hooks/format_autopkg_yaml_recipes.py
@@ -4,7 +4,6 @@
 import argparse
 import io
 import re
-from typing import List, Optional
 
 import ruamel.yaml
 from ruamel.yaml.constructor import DuplicateKeyError
@@ -74,7 +73,7 @@ def _reorder_recipe(recipe) -> None:
 
 def _insert_section_blank_lines(output: str) -> str:
     """Ensure a single blank line precedes each top-level recipe section."""
-    result: List[str] = []
+    result: list[str] = []
     for line in output.split("\n"):
         if not line.startswith(_TOP_LEVEL_TRIGGERS):
             result.append(line)
@@ -127,7 +126,7 @@ def build_argument_parser() -> argparse.ArgumentParser:
     return parser
 
 
-def main(argv: Optional[List[str]] = None) -> int:
+def main(argv: list[str] | None = None) -> int:
     """Main process."""
     argparser = build_argument_parser()
     args = argparser.parse_args(argv)
diff --git a/pre_commit_macadmin_hooks/format_xml_plist.py b/pre_commit_macadmin_hooks/format_xml_plist.py
index 28e81f0..66d1fbf 100644
--- a/pre_commit_macadmin_hooks/format_xml_plist.py
+++ b/pre_commit_macadmin_hooks/format_xml_plist.py
@@ -3,7 +3,6 @@
 
 import argparse
 import plistlib
-from typing import List, Optional
 from xml.parsers.expat import ExpatError
 
 
@@ -17,7 +16,7 @@ def build_argument_parser() -> argparse.ArgumentParser:
     return parser
 
 
-def main(argv: Optional[List[str]] = None) -> int:
+def main(argv: list[str] | None = None) -> int:
     """Main process."""
 
     # Parse command line arguments.
diff --git a/pre_commit_macadmin_hooks/munki_makecatalogs.py b/pre_commit_macadmin_hooks/munki_makecatalogs.py
index 3df5ab3..51381ea 100755
--- a/pre_commit_macadmin_hooks/munki_makecatalogs.py
+++ b/pre_commit_macadmin_hooks/munki_makecatalogs.py
@@ -5,7 +5,6 @@
 import argparse
 import os
 import subprocess
-from typing import List, Optional
 
 
 def build_argument_parser() -> argparse.ArgumentParser:
@@ -21,7 +20,7 @@ def build_argument_parser() -> argparse.ArgumentParser:
     return parser
 
 
-def main(argv: Optional[List[str]] = None) -> int:
+def main(argv: list[str] | None = None) -> int:
     """Main process."""
 
     # Path to makecatalogs.
diff --git a/pre_commit_macadmin_hooks/util.py b/pre_commit_macadmin_hooks/util.py
index 3f865f7..026caab 100644
--- a/pre_commit_macadmin_hooks/util.py
+++ b/pre_commit_macadmin_hooks/util.py
@@ -3,7 +3,7 @@
 import json
 import plistlib
 from datetime import datetime
-from typing import Any, Dict, List, Optional
+from typing import Any
 
 import ruamel.yaml
 
@@ -38,7 +38,7 @@
 ]
 
 
-def load_autopkg_recipe(path: str) -> Optional[Dict[str, Any]]:
+def load_autopkg_recipe(path: str) -> dict[str, Any] | None:
     """Loads an AutoPkg recipe in plist, yaml, or json format."""
     recipe = None
 
@@ -68,7 +68,7 @@ def load_autopkg_recipe(path: str) -> Optional[Dict[str, Any]]:
 
 
 def validate_required_keys(
-    input_dict: Dict[str, Any], filename: str, required_keys: List[str]
+    input_dict: dict[str, Any], filename: str, required_keys: list[str]
 ) -> bool:
     """Verifies that required_keys are present in dictionary."""
     passed = True
@@ -79,7 +79,7 @@ def validate_required_keys(
     return passed
 
 
-def detect_deprecated_keys(input_dict: Dict[str, Any], filename: str) -> bool:
+def detect_deprecated_keys(input_dict: dict[str, Any], filename: str) -> bool:
     """Verifies that no deprecated keys are present in dictionary."""
     # List from: https://github.com/munki/munki/wiki/Supported-Pkginfo-Keys
     deprecated_keys = (
@@ -95,7 +95,7 @@ def detect_deprecated_keys(input_dict: Dict[str, Any], filename: str) -> bool:
     return passed
 
 
-def detect_typoed_keys(input_dict: Dict[str, Any], filename: str) -> bool:
+def detect_typoed_keys(input_dict: dict[str, Any], filename: str) -> bool:
     """Verifies that specific key name typos are not present in dictionary."""
     key_corrections = {
         "appleitem": "apple_item",
@@ -143,7 +143,7 @@ def detect_typoed_keys(input_dict: Dict[str, Any], filename: str) -> bool:
     return passed
 
 
-def validate_restart_action_key(pkginfo: Dict[str, Any], filename: str) -> bool:
+def validate_restart_action_key(pkginfo: dict[str, Any], filename: str) -> bool:
     """Verifies that the RestartAction key is set correctly."""
     passed = True
     allowed_values = (
@@ -162,7 +162,7 @@ def validate_restart_action_key(pkginfo: Dict[str, Any], filename: str) -> bool:
     return passed
 
 
-def validate_uninstall_method(pkginfo: Dict[str, Any], filename: str) -> bool:
+def validate_uninstall_method(pkginfo: dict[str, Any], filename: str) -> bool:
     """Verifies that uninstall_method and uninstall_script is used appropriately."""
     passed = True
     uninst_method = pkginfo.get("uninstall_method")
@@ -182,7 +182,7 @@ def validate_uninstall_method(pkginfo: Dict[str, Any], filename: str) -> bool:
 
 
 def validate_supported_architectures(
-    pkginfo: Dict[str, Any], filename: str, recipe_mode: bool = False
+    pkginfo: dict[str, Any], filename: str, recipe_mode: bool = False
 ) -> bool:
     """Verifies that supported_architectures values are valid.
 
@@ -204,7 +204,7 @@ def validate_supported_architectures(
     return passed
 
 
-def validate_pkginfo_key_types(pkginfo: Dict[str, Any], filename: str) -> bool:
+def validate_pkginfo_key_types(pkginfo: dict[str, Any], filename: str) -> bool:
     """Validation of pkginfo key types.
 
     Used for AutoPkg- and Munki-related hooks.
@@ -288,7 +288,7 @@ def validate_pkginfo_key_types(pkginfo: Dict[str, Any], filename: str) -> bool:
 
 
 def validate_shebangs(
-    script_content: str, filename: str, addl_shebangs: Optional[List[str]] = None
+    script_content: str, filename: str, addl_shebangs: list[str] | None = None
 ) -> bool:
     """Verifies that scripts begin with a valid shebang."""
     if addl_shebangs is None: