diff --git a/.github/workflows/auto_updates.yml b/.github/workflows/auto_updates.yml
index cb41847..2cd2698 100644
--- a/.github/workflows/auto_updates.yml
+++ b/.github/workflows/auto_updates.yml
@@ -15,7 +15,7 @@ jobs:
     name: Update dependencies and hooks
     runs-on: ubuntu-latest
     env:
-      PYTHON_VERSION: "3.12"
+      PYTHON_VERSION: "3.13"
       POETRY_VERSION: "1.8.5"
     defaults:
       run:
diff --git a/.github/workflows/preview.yml b/.github/workflows/preview.yml
index 7c170b2..7b7e4ad 100644
--- a/.github/workflows/preview.yml
+++ b/.github/workflows/preview.yml
@@ -25,7 +25,7 @@ on:
       - main
 
 env:
-  PYTHON_VERSION: "3.12"
+  PYTHON_VERSION: "3.13"
   POETRY_VERSION: "1.8.5"
 
 jobs:
diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index 6556e79..1b982f4 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -28,7 +28,7 @@ on:
         default: false
 
 env:
-  PYTHON_VERSION: "3.12"
+  PYTHON_VERSION: "3.13"
   POETRY_VERSION: "1.8.5"
 
 jobs:
diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index b6c584f..4a02d98 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -15,7 +15,7 @@ defaults:
     shell: bash
 
 env:
-  PYTHON_VERSION: "3.12"
+  PYTHON_VERSION: "3.13"
   POETRY_VERSION: "1.8.5"
 
 jobs:
@@ -64,7 +64,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python-version: ["3.9", "3.10", "3.11", "3.12"]
+        python-version: ["3.10", "3.11", "3.12", "3.13"]
     steps:
       - name: Checkout the repo
         uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 45f7af4..09861c2 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -104,26 +104,26 @@ Here's how to set up `phylum-ci` for local development.
 3. Ensure all supported Python versions are installed locally
    1. The strategy is to support the current/latest release plus the previous three minor versions of Python
    2. The current list
-      1. at the time of this writing is 3.9, 3.10, 3.11, and 3.12
+      1. at the time of this writing is 3.10, 3.11, 3.12, and 3.13
       2. can be inferred with the Python Developer's Guide, which maintains the
          [status of active Python releases](https://devguide.python.org/versions/)
    3. It is recommended to use [`pyenv`](https://github.com/pyenv/pyenv) to manage multiple Python installations
 
     ```sh
     # Use `pyenv install --list` to get available versions and usually install the
-    # latest patch version. For example, use `pyenv install --list |grep 3.9.` to
-    # show latest patch version for the cpython 3.9 minor release.
+    # latest patch version. For example, use `pyenv install --list |grep 3.10.` to
+    # show latest patch version for the cpython 3.10 minor release.
 
     # NOTE: These versions are examples; the latest patch version available from
     #       pyenv should be used in place of `.x`.
-    pyenv install 3.9.x
     pyenv install 3.10.x
     pyenv install 3.11.x
     pyenv install 3.12.x
+    pyenv install 3.13.x
     pyenv rehash
 
     # Ensure all environments are available globally (helps tox to find them)
-    pyenv global 3.12.x 3.11.x 3.10.x 3.9.x
+    pyenv global 3.13.x 3.12.x 3.11.x 3.10.x
     ```
 
 4. Ensure [poetry v1.7+](https://python-poetry.org/docs/) is installed
@@ -217,7 +217,7 @@ Before you submit a pull request, check that it meets these guidelines:
 * Have you created sufficient tests?
 * Have you updated all affected documentation?
 
-The pull request should work for Python 3.9, 3.10, 3.11, and 3.12.
+The pull request should work for Python 3.10, 3.11, 3.12 and 3.13.
 Check <https://github.com/phylum-dev/phylum-ci/actions> and make sure that the tests
 pass for all supported Python versions.
 
@@ -254,10 +254,10 @@ poetry run -- tox run -e py310 -- --help
 poetry run -- tox run-parallel -- tests/unit/test_package_metadata.py
 
 # run a specific test module across a specific test environment
-poetry run -- tox run -e py39 -- tests/unit/test_package_metadata.py
+poetry run -- tox run -e py310 -- tests/unit/test_package_metadata.py
 
 # run a specific test function within a test module, in a specific test environment
-poetry run -- tox run -e py310 -- tests/unit/test_package_metadata.py::test_python_version
+poetry run -- tox run -e py311 -- tests/unit/test_package_metadata.py::test_python_version
 ```
 
 To run a script entry point with the local checkout of the code (in develop mode), use `poetry`:
diff --git a/Dockerfile b/Dockerfile
index 68229af..51bbebb 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -69,7 +69,7 @@
 # $ scripts/docker_tests.sh --image phylum-ci
 ##########################################################################################
 
-FROM python:3.12-slim-bookworm AS builder
+FROM python:3.13-slim-bookworm AS builder
 
 # PKG_SRC is the path to a built distribution/wheel and PKG_NAME is the name of the built
 # distribution/wheel. Both can optionally be specified in glob form. When not defined,
@@ -121,7 +121,7 @@ RUN find ${PHYLUM_VENV} -type f -name '*.pyc' -delete
 # in the final layer and also known to be part of the $PATH
 COPY entrypoint.sh ${PHYLUM_VENV}/bin/
 
-FROM python:3.12-slim-bookworm
+FROM python:3.13-slim-bookworm
 
 # CLI_VER specifies the Phylum CLI version to install in the image.
 # Values should be provided in a format acceptable to the `phylum-init` script.
diff --git a/Dockerfile.slim b/Dockerfile.slim
index e8dd21f..53216db 100644
--- a/Dockerfile.slim
+++ b/Dockerfile.slim
@@ -77,7 +77,7 @@
 # $ scripts/docker_tests.sh --image phylum-ci --slim
 ##########################################################################################
 
-FROM python:3.12-slim-bookworm AS builder
+FROM python:3.13-slim-bookworm AS builder
 
 # PKG_SRC is the path to a built distribution/wheel and PKG_NAME is the name of the built
 # distribution/wheel. Both can optionally be specified in glob form. When not defined,
@@ -129,7 +129,7 @@ RUN find ${PHYLUM_VENV} -type f -name '*.pyc' -delete
 # in the final layer and also known to be part of the $PATH
 COPY entrypoint.sh ${PHYLUM_VENV}/bin/
 
-FROM python:3.12-slim-bookworm
+FROM python:3.13-slim-bookworm
 
 # CLI_VER specifies the Phylum CLI version to install in the image.
 # Values should be provided in a format acceptable to the `phylum-init` script.
diff --git a/README.md b/README.md
index a23a46e..9f4661f 100644
--- a/README.md
+++ b/README.md
@@ -47,7 +47,7 @@ pipx run --spec phylum phylum-init <options>
 pipx run --spec phylum phylum-ci <options>
 ```
 
-These installation methods require Python 3.9+ to run.
+These installation methods require Python 3.10+ to run.
 For a self contained environment, consider using the Docker image as described below.
 
 Windows binaries are offered as [release artifacts][latest_rels] for a "standalone" solution that does not require
diff --git a/poetry.lock b/poetry.lock
index 75eee72..22c6f70 100644
--- a/poetry.lock
+++ b/poetry.lock
@@ -300,51 +300,51 @@ files = [
 
 [[package]]
 name = "cryptography"
-version = "43.0.3"
+version = "44.0.0"
 description = "cryptography is a package which provides cryptographic recipes and primitives to Python developers."
 optional = false
-python-versions = ">=3.7"
-files = [
-    {file = "cryptography-43.0.3-cp37-abi3-macosx_10_9_universal2.whl", hash = "sha256:bf7a1932ac4176486eab36a19ed4c0492da5d97123f1406cf15e41b05e787d2e"},
-    {file = "cryptography-43.0.3-cp37-abi3-manylinux_2_17_aarch64.manylinux2014_aarch64.whl", hash = "sha256:63efa177ff54aec6e1c0aefaa1a241232dcd37413835a9b674b6e3f0ae2bfd3e"},
-    {file = "cryptography-43.0.3-cp37-abi3-manylinux_2_17_x86_64.manylinux2014_x86_64.whl", hash = "sha256:7e1ce50266f4f70bf41a2c6dc4358afadae90e2a1e5342d3c08883df1675374f"},
-    {file = "cryptography-43.0.3-cp37-abi3-manylinux_2_28_aarch64.whl", hash = "sha256:443c4a81bb10daed9a8f334365fe52542771f25aedaf889fd323a853ce7377d6"},
-    {file = "cryptography-43.0.3-cp37-abi3-manylinux_2_28_x86_64.whl", hash = "sha256:74f57f24754fe349223792466a709f8e0c093205ff0dca557af51072ff47ab18"},
-    {file = "cryptography-43.0.3-cp37-abi3-musllinux_1_2_aarch64.whl", hash = "sha256:9762ea51a8fc2a88b70cf2995e5675b38d93bf36bd67d91721c309df184f49bd"},
-    {file = "cryptography-43.0.3-cp37-abi3-musllinux_1_2_x86_64.whl", hash = "sha256:81ef806b1fef6b06dcebad789f988d3b37ccaee225695cf3e07648eee0fc6b73"},
-    {file = "cryptography-43.0.3-cp37-abi3-win32.whl", hash = "sha256:cbeb489927bd7af4aa98d4b261af9a5bc025bd87f0e3547e11584be9e9427be2"},
-    {file = "cryptography-43.0.3-cp37-abi3-win_amd64.whl", hash = "sha256:f46304d6f0c6ab8e52770addfa2fc41e6629495548862279641972b6215451cd"},
-    {file = "cryptography-43.0.3-cp39-abi3-macosx_10_9_universal2.whl", hash = "sha256:8ac43ae87929a5982f5948ceda07001ee5e83227fd69cf55b109144938d96984"},
-    {file = "cryptography-43.0.3-cp39-abi3-manylinux_2_17_aarch64.manylinux2014_aarch64.whl", hash = "sha256:846da004a5804145a5f441b8530b4bf35afbf7da70f82409f151695b127213d5"},
-    {file = "cryptography-43.0.3-cp39-abi3-manylinux_2_17_x86_64.manylinux2014_x86_64.whl", hash = "sha256:0f996e7268af62598f2fc1204afa98a3b5712313a55c4c9d434aef49cadc91d4"},
-    {file = "cryptography-43.0.3-cp39-abi3-manylinux_2_28_aarch64.whl", hash = "sha256:f7b178f11ed3664fd0e995a47ed2b5ff0a12d893e41dd0494f406d1cf555cab7"},
-    {file = "cryptography-43.0.3-cp39-abi3-manylinux_2_28_x86_64.whl", hash = "sha256:c2e6fc39c4ab499049df3bdf567f768a723a5e8464816e8f009f121a5a9f4405"},
-    {file = "cryptography-43.0.3-cp39-abi3-musllinux_1_2_aarch64.whl", hash = "sha256:e1be4655c7ef6e1bbe6b5d0403526601323420bcf414598955968c9ef3eb7d16"},
-    {file = "cryptography-43.0.3-cp39-abi3-musllinux_1_2_x86_64.whl", hash = "sha256:df6b6c6d742395dd77a23ea3728ab62f98379eff8fb61be2744d4679ab678f73"},
-    {file = "cryptography-43.0.3-cp39-abi3-win32.whl", hash = "sha256:d56e96520b1020449bbace2b78b603442e7e378a9b3bd68de65c782db1507995"},
-    {file = "cryptography-43.0.3-cp39-abi3-win_amd64.whl", hash = "sha256:0c580952eef9bf68c4747774cde7ec1d85a6e61de97281f2dba83c7d2c806362"},
-    {file = "cryptography-43.0.3-pp310-pypy310_pp73-macosx_10_9_x86_64.whl", hash = "sha256:d03b5621a135bffecad2c73e9f4deb1a0f977b9a8ffe6f8e002bf6c9d07b918c"},
-    {file = "cryptography-43.0.3-pp310-pypy310_pp73-manylinux_2_28_aarch64.whl", hash = "sha256:a2a431ee15799d6db9fe80c82b055bae5a752bef645bba795e8e52687c69efe3"},
-    {file = "cryptography-43.0.3-pp310-pypy310_pp73-manylinux_2_28_x86_64.whl", hash = "sha256:281c945d0e28c92ca5e5930664c1cefd85efe80e5c0d2bc58dd63383fda29f83"},
-    {file = "cryptography-43.0.3-pp310-pypy310_pp73-win_amd64.whl", hash = "sha256:f18c716be16bc1fea8e95def49edf46b82fccaa88587a45f8dc0ff6ab5d8e0a7"},
-    {file = "cryptography-43.0.3-pp39-pypy39_pp73-macosx_10_9_x86_64.whl", hash = "sha256:4a02ded6cd4f0a5562a8887df8b3bd14e822a90f97ac5e544c162899bc467664"},
-    {file = "cryptography-43.0.3-pp39-pypy39_pp73-manylinux_2_28_aarch64.whl", hash = "sha256:53a583b6637ab4c4e3591a15bc9db855b8d9dee9a669b550f311480acab6eb08"},
-    {file = "cryptography-43.0.3-pp39-pypy39_pp73-manylinux_2_28_x86_64.whl", hash = "sha256:1ec0bcf7e17c0c5669d881b1cd38c4972fade441b27bda1051665faaa89bdcaa"},
-    {file = "cryptography-43.0.3-pp39-pypy39_pp73-win_amd64.whl", hash = "sha256:2ce6fae5bdad59577b44e4dfed356944fbf1d925269114c28be377692643b4ff"},
-    {file = "cryptography-43.0.3.tar.gz", hash = "sha256:315b9001266a492a6ff443b61238f956b214dbec9910a081ba5b6646a055a805"},
+python-versions = "!=3.9.0,!=3.9.1,>=3.7"
+files = [
+    {file = "cryptography-44.0.0-cp37-abi3-macosx_10_9_universal2.whl", hash = "sha256:84111ad4ff3f6253820e6d3e58be2cc2a00adb29335d4cacb5ab4d4d34f2a123"},
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+    {file = "cryptography-44.0.0-cp37-abi3-manylinux_2_17_x86_64.manylinux2014_x86_64.whl", hash = "sha256:831c3c4d0774e488fdc83a1923b49b9957d33287de923d58ebd3cec47a0ae43f"},
+    {file = "cryptography-44.0.0-cp37-abi3-manylinux_2_28_aarch64.whl", hash = "sha256:761817a3377ef15ac23cd7834715081791d4ec77f9297ee694ca1ee9c2c7e5eb"},
+    {file = "cryptography-44.0.0-cp37-abi3-manylinux_2_28_x86_64.whl", hash = "sha256:3c672a53c0fb4725a29c303be906d3c1fa99c32f58abe008a82705f9ee96f40b"},
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+    {file = "cryptography-44.0.0-cp37-abi3-musllinux_1_2_x86_64.whl", hash = "sha256:f3f6fdfa89ee2d9d496e2c087cebef9d4fcbb0ad63c40e821b39f74bf48d9c5e"},
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+    {file = "cryptography-44.0.0-pp310-pypy310_pp73-manylinux_2_28_x86_64.whl", hash = "sha256:f5e7cb1e5e56ca0933b4873c0220a78b773b24d40d186b6738080b73d3d0a756"},
+    {file = "cryptography-44.0.0-pp310-pypy310_pp73-manylinux_2_34_aarch64.whl", hash = "sha256:8b3e6eae66cf54701ee7d9c83c30ac0a1e3fa17be486033000f2a73a12ab507c"},
+    {file = "cryptography-44.0.0-pp310-pypy310_pp73-manylinux_2_34_x86_64.whl", hash = "sha256:be4ce505894d15d5c5037167ffb7f0ae90b7be6f2a98f9a5c3442395501c32fa"},
+    {file = "cryptography-44.0.0-pp310-pypy310_pp73-win_amd64.whl", hash = "sha256:62901fb618f74d7d81bf408c8719e9ec14d863086efe4185afd07c352aee1d2c"},
+    {file = "cryptography-44.0.0.tar.gz", hash = "sha256:cd4e834f340b4293430701e772ec543b0fbe6c2dea510a5286fe0acabe153a02"},
 ]
 
 [package.dependencies]
 cffi = {version = ">=1.12", markers = "platform_python_implementation != \"PyPy\""}
 
 [package.extras]
-docs = ["sphinx (>=5.3.0)", "sphinx-rtd-theme (>=1.1.1)"]
-docstest = ["pyenchant (>=1.6.11)", "readme-renderer", "sphinxcontrib-spelling (>=4.0.1)"]
-nox = ["nox"]
-pep8test = ["check-sdist", "click", "mypy", "ruff"]
-sdist = ["build"]
+docs = ["sphinx (>=5.3.0)", "sphinx-rtd-theme (>=3.0.0)"]
+docstest = ["pyenchant (>=3)", "readme-renderer (>=30.0)", "sphinxcontrib-spelling (>=7.3.1)"]
+nox = ["nox (>=2024.4.15)", "nox[uv] (>=2024.3.2)"]
+pep8test = ["check-sdist", "click (>=8.0.1)", "mypy (>=1.4)", "ruff (>=0.3.6)"]
+sdist = ["build (>=1.0.0)"]
 ssh = ["bcrypt (>=3.1.5)"]
-test = ["certifi", "cryptography-vectors (==43.0.3)", "pretend", "pytest (>=6.2.0)", "pytest-benchmark", "pytest-cov", "pytest-xdist"]
+test = ["certifi (>=2024)", "cryptography-vectors (==44.0.0)", "pretend (>=0.7)", "pytest (>=7.4.0)", "pytest-benchmark (>=4.0)", "pytest-cov (>=2.10.1)", "pytest-xdist (>=3.5.0)"]
 test-randomorder = ["pytest-randomly"]
 
 [[package]]
@@ -531,9 +531,6 @@ files = [
     {file = "importlib_resources-6.5.2.tar.gz", hash = "sha256:185f87adef5bcc288449d98fb4fba07cea78bc036455dd44c5fc4a2fe78fed2c"},
 ]
 
-[package.dependencies]
-zipp = {version = ">=3.1.0", markers = "python_version < \"3.10\""}
-
 [package.extras]
 check = ["pytest-checkdocs (>=2.4)", "pytest-ruff (>=0.2.1)"]
 cover = ["pytest-cov"]
@@ -1823,25 +1820,6 @@ platformdirs = ">=3.9.1,<5"
 docs = ["furo (>=2023.7.26)", "proselint (>=0.13)", "sphinx (>=7.1.2,!=7.3)", "sphinx-argparse (>=0.4)", "sphinxcontrib-towncrier (>=0.2.1a0)", "towncrier (>=23.6)"]
 test = ["covdefaults (>=2.3)", "coverage (>=7.2.7)", "coverage-enable-subprocess (>=1)", "flaky (>=3.7)", "packaging (>=23.1)", "pytest (>=7.4)", "pytest-env (>=0.8.2)", "pytest-freezer (>=0.4.8)", "pytest-mock (>=3.11.1)", "pytest-randomly (>=3.12)", "pytest-timeout (>=2.1)", "setuptools (>=68)", "time-machine (>=2.10)"]
 
-[[package]]
-name = "zipp"
-version = "3.21.0"
-description = "Backport of pathlib-compatible object wrapper for zip files"
-optional = false
-python-versions = ">=3.9"
-files = [
-    {file = "zipp-3.21.0-py3-none-any.whl", hash = "sha256:ac1bbe05fd2991f160ebce24ffbac5f6d11d83dc90891255885223d42b3cd931"},
-    {file = "zipp-3.21.0.tar.gz", hash = "sha256:2c9958f6430a2040341a52eb608ed6dd93ef4392e02ffe219417c1b28b5dd1f4"},
-]
-
-[package.extras]
-check = ["pytest-checkdocs (>=2.4)", "pytest-ruff (>=0.2.1)"]
-cover = ["pytest-cov"]
-doc = ["furo", "jaraco.packaging (>=9.3)", "jaraco.tidelift (>=1.4)", "rst.linker (>=1.9)", "sphinx (>=3.5)", "sphinx-lint"]
-enabler = ["pytest-enabler (>=2.2)"]
-test = ["big-O", "importlib-resources", "jaraco.functools", "jaraco.itertools", "jaraco.test", "more-itertools", "pytest (>=6,!=8.1.*)", "pytest-ignore-flaky"]
-type = ["pytest-mypy"]
-
 [[package]]
 name = "zstandard"
 version = "0.23.0"
@@ -1956,5 +1934,5 @@ cffi = ["cffi (>=1.11)"]
 
 [metadata]
 lock-version = "2.0"
-python-versions = ">=3.9,<3.13"
-content-hash = "f89fca2c51c09bd7470e5ede6259ae24d84f6c9cd749b70dc8bfdeb0772b65a8"
+python-versions = ">=3.10,<3.14"
+content-hash = "de4dff7ccf2316cb801fbda552c775dcda28152c4d93f6470688cb784f9a4f63"
diff --git a/pyproject.toml b/pyproject.toml
index 221ce56..544f3ad 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -27,10 +27,10 @@ classifiers = [
     "Topic :: Software Development",
     "Topic :: Software Development :: Quality Assurance",
     "Programming Language :: Python :: 3",
-    "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",
 ]
 packages = [
     { include = "phylum", from = "src" },
@@ -46,7 +46,7 @@ phylum-init = "phylum.init.cli:main"
 phylum-ci = "phylum.ci.cli:script_main"
 
 [tool.poetry.dependencies]
-python = ">=3.9,<3.13"
+python = ">=3.10,<3.14"
 requests = "*"
 cryptography = "*"
 packaging = "*"
@@ -103,7 +103,7 @@ paths = ["src", "tests"]
 exclude = ["conftest.py"]
 
 [tool.refurb]
-python_version = "3.9"
+python_version = "3.10"
 format = "github"
 # FURB184 (use-fluent-interface) is ignored because the benefits of "chaining" calls identified by this rule are not
 # outweighed by the type checking based autocompletion and syntax highlighting provided by the IDE with the calls split.
@@ -112,7 +112,7 @@ ignore = [184]
 [tool.ruff]
 # Reference: https://docs.astral.sh/ruff/configuration/
 line-length = 120
-target-version = "py39"
+target-version = "py310"
 force-exclude = true
 src = ["src", "tests"]
 
diff --git a/src/phylum/ci/ci_azure.py b/src/phylum/ci/ci_azure.py
index bbbe72d..027b87c 100644
--- a/src/phylum/ci/ci_azure.py
+++ b/src/phylum/ci/ci_azure.py
@@ -24,7 +24,6 @@
 import re
 import shlex
 import subprocess
-from typing import Optional
 import urllib.parse
 
 import requests
@@ -176,7 +175,7 @@ def phylum_label(self) -> str:
         return label
 
     @cached_property
-    def common_ancestor_commit(self) -> Optional[str]:
+    def common_ancestor_commit(self) -> str | None:
         """Find the common ancestor commit."""
         remote = git_remote()
 
@@ -294,7 +293,7 @@ def phylum_comment_exists(self) -> bool:
         return False
 
     @property
-    def repo_url(self) -> Optional[str]:
+    def repo_url(self) -> str | None:
         """Get the repository URL for reference in Phylum project metadata."""
         # Ref: https://learn.microsoft.com/azure/devops/pipelines/build/variables
         if self.triggering_repo == "TfsGit":
@@ -365,7 +364,7 @@ def get_pr_branches() -> tuple[str, str]:
 # The function is meant to be used internally, where it is known that the comments on the PR at the time
 # of first execution will suffice for the duration of the rest of the lifetime of the running integration.
 @lru_cache(maxsize=1)
-def get_most_recent_phylum_comment_azure(azure_token: str) -> Optional[str]:
+def get_most_recent_phylum_comment_azure(azure_token: str) -> str | None:
     """Get the raw text of the most recently posted Phylum-generated comment for Azure Repos PRs.
 
     Return `None` when one does not exist.
diff --git a/src/phylum/ci/ci_base.py b/src/phylum/ci/ci_base.py
index 69fdfb4..3453f8c 100644
--- a/src/phylum/ci/ci_base.py
+++ b/src/phylum/ci/ci_base.py
@@ -19,7 +19,6 @@
 import shutil
 import subprocess
 import tempfile
-from typing import Optional
 
 import pathspec
 from rich.markdown import Markdown
@@ -62,7 +61,7 @@ def __init__(self, args: Namespace) -> None:
         self._force_analysis = args.force_analysis
         self._returncode = ReturnCode.SUCCESS
         self._analysis_report = "No analysis output yet"
-        self._env: Optional[Mapping[str, str]] = None
+        self._env: Mapping[str, str] | None = None
         self.ci_platform_name = "Unknown"
         self.disable_lockfile_generation = False
 
@@ -186,7 +185,7 @@ def depfiles(self) -> Depfiles:
 
         Detected dependency files can be modified with exclusion patterns provided as an argument.
         """
-        arg_depfiles: Optional[list[list[Path]]] = self.args.depfile
+        arg_depfiles: list[list[Path]] | None = self.args.depfile
         provided_arg_depfiles: DepfileEntries = []
         if arg_depfiles:
             # Flatten the list of lists
@@ -225,7 +224,7 @@ def depfiles(self) -> Depfiles:
 
     def _exclude_depfiles(self, provided_depfiles: DepfileEntries) -> DepfileEntries:
         """Apply exclusion patterns to provided dependency files and return the remaining ones."""
-        arg_exclusions: Optional[list[list[str]]] = self.args.exclude
+        arg_exclusions: list[list[str]] | None = self.args.exclude
         if not arg_exclusions:
             LOG.debug("No dependency file exclusion patterns provided.")
             return provided_depfiles
@@ -400,7 +399,7 @@ def phylum_project(self) -> str:
         return project_name
 
     @cached_property
-    def phylum_org(self) -> Optional[str]:
+    def phylum_org(self) -> str | None:
         """Get the effective Phylum organization in use.
 
         The Phylum organization name can be specified as an option or contained in the `settings.yaml` file.
@@ -442,7 +441,7 @@ def phylum_org(self) -> Optional[str]:
         return None
 
     @cached_property
-    def phylum_group(self) -> Optional[str]:
+    def phylum_group(self) -> str | None:
         """Get the effective Phylum group in use.
 
         The Phylum group name can be specified as an option or contained in the `.phylum_project` file.
@@ -556,7 +555,7 @@ def phylum_label(self) -> str:
 
     @property
     @abstractmethod
-    def repo_url(self) -> Optional[str]:
+    def repo_url(self) -> str | None:
         """Get the repository URL for reference in Phylum project metadata.
 
         The value should only exist for implementations that make use of a web hosted CI environment. The local use
@@ -589,7 +588,7 @@ def depfile_hash_object(self) -> str:
 
     @cached_property
     @abstractmethod
-    def common_ancestor_commit(self) -> Optional[str]:
+    def common_ancestor_commit(self) -> str | None:
         """Find the common ancestor commit.
 
         When found, it should be returned as a string of the SHA1 sum representing the commit.
@@ -615,7 +614,7 @@ def phylum_comment_exists(self) -> bool:
         """
         raise NotImplementedError
 
-    def _update_depfiles_change_status(self, commit: str, err_msg: Optional[str] = None) -> None:
+    def _update_depfiles_change_status(self, commit: str, err_msg: str | None = None) -> None:
         """Update each dependency file's change status.
 
         The input `commit` is the one to use in a `git diff` command to view the changes relative to the working tree.
@@ -930,21 +929,10 @@ def analyze(self) -> None:
             dep_txt = "dependency" if num_new_packages == 1 else "dependencies"
             LOG.debug("%s new %s: %s", num_new_packages, dep_txt, new_packages)
 
-        # TODO(maxrake): Better formatting with parenthesized context managers is available in Python 3.10+
-        #     https://github.com/phylum-dev/phylum-ci/issues/357
-        #     https://docs.python.org/3.10/whatsnew/3.10.html#parenthesized-context-managers
-        #     https://stackoverflow.com/q/67808977
-        with tempfile.NamedTemporaryFile(
-            mode="w+",
-            encoding="utf-8",
-            prefix="base_",
-            suffix=".json",
-        ) as base_fd, tempfile.NamedTemporaryFile(
-            mode="w+",
-            encoding="utf-8",
-            prefix="curr_",
-            suffix=".json",
-        ) as curr_fd:
+        with (
+            tempfile.NamedTemporaryFile(mode="w+", encoding="utf-8", prefix="base_", suffix=".json") as base_fd,
+            tempfile.NamedTemporaryFile(mode="w+", encoding="utf-8", prefix="curr_", suffix=".json") as curr_fd,
+        ):
             json.dump(base_packages, base_fd, cls=DataclassJSONEncoder)
             base_fd.flush()
             cmd.append(base_fd.name)
@@ -1024,21 +1012,19 @@ def _parse_analysis_result(self, analysis_result: str) -> None:
 
         self._analysis_report = analysis.report
 
-        # TODO(maxrake): The logic below would make for a good match statement, which was introduced in Python 3.10
-        #     https://github.com/phylum-dev/phylum-ci/issues/357
-        if analysis.incomplete_count == 0:
-            if analysis.is_failure:
+        match (analysis.incomplete_count, analysis.is_failure):
+            case (0, True):
                 LOG.error("Analysis is complete and there were failures")
                 self.returncode = ReturnCode.ANALYSIS_POLICY_FAILURE
-            else:
+            case (0, False):
                 LOG.info("Analysis is complete and there were NO failures")
                 self.returncode = ReturnCode.SUCCESS
-        elif analysis.is_failure:
-            LOG.error("There were failures in one or more completed packages")
-            self.returncode = ReturnCode.ANALYSIS_FAILURE_INCOMPLETE
-        else:
-            LOG.warning("There were no failures in the packages that have completed so far")
-            self.returncode = ReturnCode.ANALYSIS_INCOMPLETE
+            case (_, True):
+                LOG.error("There were failures in one or more completed packages")
+                self.returncode = ReturnCode.ANALYSIS_FAILURE_INCOMPLETE
+            case (_, False):
+                LOG.warning("There were no failures in the packages that have completed so far")
+                self.returncode = ReturnCode.ANALYSIS_INCOMPLETE
 
 
 # Type alias
diff --git a/src/phylum/ci/ci_bitbucket.py b/src/phylum/ci/ci_bitbucket.py
index c6b4468..f88bca6 100644
--- a/src/phylum/ci/ci_bitbucket.py
+++ b/src/phylum/ci/ci_bitbucket.py
@@ -24,7 +24,6 @@
 import re
 import shlex
 import subprocess
-from typing import Optional
 import urllib.parse
 
 import requests
@@ -122,7 +121,7 @@ def phylum_label(self) -> str:
         return label
 
     @cached_property
-    def common_ancestor_commit(self) -> Optional[str]:
+    def common_ancestor_commit(self) -> str | None:
         """Find the common ancestor commit.
 
         Some pre-defined variables are used: https://support.atlassian.com/bitbucket-cloud/docs/variables-and-secrets/
@@ -221,7 +220,7 @@ def phylum_comment_exists(self) -> bool:
         return bool(self.most_recent_phylum_comment)
 
     @property
-    def repo_url(self) -> Optional[str]:
+    def repo_url(self) -> str | None:
         """Get the repository URL for reference in Phylum project metadata."""
         # This is the "URL for the origin", which uses `HTTP:` instead of
         # `HTTPS:`, even though the value redirects to the `HTTPS:` site.
@@ -285,7 +284,7 @@ def headers(self) -> dict:
         return headers
 
     @cached_property
-    def most_recent_phylum_comment(self) -> Optional[str]:
+    def most_recent_phylum_comment(self) -> str | None:
         """Get the raw text of the most recently posted Phylum-generated comment.
 
         Return `None` when one does not exist.
diff --git a/src/phylum/ci/ci_github.py b/src/phylum/ci/ci_github.py
index 86410fd..e59d75f 100644
--- a/src/phylum/ci/ci_github.py
+++ b/src/phylum/ci/ci_github.py
@@ -19,7 +19,6 @@
 from pathlib import Path
 import re
 import subprocess
-from typing import Optional
 
 import requests
 
@@ -157,7 +156,7 @@ def phylum_label(self) -> str:
         return label
 
     @cached_property
-    def common_ancestor_commit(self) -> Optional[str]:
+    def common_ancestor_commit(self) -> str | None:
         """Find the common ancestor commit."""
         return self.pr_event.get("pull_request", {}).get("base", {}).get("sha")
 
@@ -194,7 +193,7 @@ def phylum_comment_exists(self) -> bool:
         return bool(get_most_recent_phylum_comment_github(self.comments_url, self.github_token))
 
     @property
-    def repo_url(self) -> Optional[str]:
+    def repo_url(self) -> str | None:
         """Get the repository URL for reference in Phylum project metadata."""
         # Ref: https://docs.github.com/actions/learn-github-actions/variables#default-environment-variables
         server_url = os.getenv("GITHUB_SERVER_URL")
@@ -226,7 +225,7 @@ def post_output(self) -> None:
 # The function is meant to be used internally, where it is known that the comments on the PR at the time
 # of first execution will suffice for the duration of the rest of the lifetime of the running integration.
 @lru_cache(maxsize=1)
-def get_most_recent_phylum_comment_github(comments_url: str, github_token: str) -> Optional[str]:
+def get_most_recent_phylum_comment_github(comments_url: str, github_token: str) -> str | None:
     """Get the raw text of the most recently posted Phylum-generated comment for GitHub PRs.
 
     Return `None` when one does not exist.
diff --git a/src/phylum/ci/ci_gitlab.py b/src/phylum/ci/ci_gitlab.py
index d4fb4db..45258f2 100644
--- a/src/phylum/ci/ci_gitlab.py
+++ b/src/phylum/ci/ci_gitlab.py
@@ -16,7 +16,6 @@
 import re
 import shlex
 import subprocess
-from typing import Optional
 
 import requests
 
@@ -103,7 +102,7 @@ def phylum_label(self) -> str:
         return label
 
     @cached_property
-    def common_ancestor_commit(self) -> Optional[str]:
+    def common_ancestor_commit(self) -> str | None:
         """Find the common ancestor commit.
 
         Some pre-defined variables are used: https://docs.gitlab.com/ee/ci/variables/predefined_variables.html
@@ -184,7 +183,7 @@ def phylum_comment_exists(self) -> bool:
         return bool(self.most_recent_phylum_note)
 
     @property
-    def repo_url(self) -> Optional[str]:
+    def repo_url(self) -> str | None:
         """Get the repository URL for reference in Phylum project metadata."""
         # Ref: https://docs.gitlab.com/ee/ci/variables/predefined_variables.html
         return os.getenv("CI_PROJECT_URL")
@@ -234,7 +233,7 @@ def headers(self) -> dict:
         return headers
 
     @cached_property
-    def most_recent_phylum_note(self) -> Optional[str]:
+    def most_recent_phylum_note(self) -> str | None:
         """Get the raw text of the most recently posted Phylum-generated note.
 
         Return `None` when one does not exist.
diff --git a/src/phylum/ci/ci_jenkins.py b/src/phylum/ci/ci_jenkins.py
index 5c1e33e..aaa8e98 100644
--- a/src/phylum/ci/ci_jenkins.py
+++ b/src/phylum/ci/ci_jenkins.py
@@ -18,7 +18,6 @@
 import re
 import shlex
 import subprocess
-from typing import Optional
 
 from phylum.ci.ci_base import CIBase
 from phylum.ci.git import git_remote, git_set_remote_head
@@ -83,7 +82,7 @@ def phylum_label(self) -> str:
         return label
 
     @cached_property
-    def common_ancestor_commit(self) -> Optional[str]:
+    def common_ancestor_commit(self) -> str | None:
         """Find the common ancestor commit.
 
         Some pre-defined variables are used:
@@ -159,7 +158,7 @@ def phylum_comment_exists(self) -> bool:
         return False
 
     @property
-    def repo_url(self) -> Optional[str]:
+    def repo_url(self) -> str | None:
         """Get the repository URL for reference in Phylum project metadata."""
         # This is the "Remote URL of the first git repository in the workspace."
         # It comes from the git plugin and may not be set depending on the context.
diff --git a/src/phylum/ci/ci_none.py b/src/phylum/ci/ci_none.py
index 2730b40..5f01da5 100644
--- a/src/phylum/ci/ci_none.py
+++ b/src/phylum/ci/ci_none.py
@@ -9,7 +9,6 @@
 from functools import cached_property
 import re
 import subprocess
-from typing import Optional
 
 from phylum.ci.ci_base import CIBase
 from phylum.ci.git import git_current_branch_name, git_remote, git_set_remote_head
@@ -41,7 +40,7 @@ def phylum_label(self) -> str:
         return label
 
     @cached_property
-    def common_ancestor_commit(self) -> Optional[str]:
+    def common_ancestor_commit(self) -> str | None:
         """Find the common ancestor commit."""
         remote = git_remote()
         cmd = ["git", "merge-base", "HEAD", f"refs/remotes/{remote}/HEAD"]
@@ -112,7 +111,7 @@ def phylum_comment_exists(self) -> bool:
         return False
 
     @property
-    def repo_url(self) -> Optional[str]:
+    def repo_url(self) -> str | None:
         """Get the repository URL for reference in Phylum project metadata."""
         # There is no repository URL in this implementation
         return None
diff --git a/src/phylum/ci/ci_precommit.py b/src/phylum/ci/ci_precommit.py
index 138fe28..d70361b 100644
--- a/src/phylum/ci/ci_precommit.py
+++ b/src/phylum/ci/ci_precommit.py
@@ -15,7 +15,6 @@
 from pathlib import Path
 import re
 import subprocess
-from typing import Optional
 
 from phylum.ci.ci_base import CIBase
 from phylum.ci.git import git_current_branch_name
@@ -112,7 +111,7 @@ def phylum_label(self) -> str:
         return label
 
     @cached_property
-    def common_ancestor_commit(self) -> Optional[str]:
+    def common_ancestor_commit(self) -> str | None:
         """Find the common ancestor commit."""
         cmd = ["git", "rev-parse", "--verify", "HEAD"]
         try:
@@ -153,7 +152,7 @@ def phylum_comment_exists(self) -> bool:
         return False
 
     @property
-    def repo_url(self) -> Optional[str]:
+    def repo_url(self) -> str | None:
         """Get the repository URL for reference in Phylum project metadata."""
         # There is no repository URL in this implementation
         return None
diff --git a/src/phylum/ci/cli.py b/src/phylum/ci/cli.py
index 85f42b8..cdc0e89 100644
--- a/src/phylum/ci/cli.py
+++ b/src/phylum/ci/cli.py
@@ -6,7 +6,6 @@
 import os
 import pathlib
 import sys
-from typing import Optional
 
 from phylum import __version__
 from phylum.ci import SCRIPT_NAME
@@ -86,7 +85,7 @@ def detect_ci_platform(args: argparse.Namespace, remainder: list[str]) -> CIBase
     return ci_env
 
 
-def get_args(args: Optional[Sequence[str]] = None) -> tuple[argparse.Namespace, list[str]]:
+def get_args(args: Sequence[str] | None = None) -> tuple[argparse.Namespace, list[str]]:
     """Get the arguments from the command line and return them."""
     parser = argparse.ArgumentParser(
         prog=SCRIPT_NAME,
@@ -243,7 +242,7 @@ def get_args(args: Optional[Sequence[str]] = None) -> tuple[argparse.Namespace,
     return parser.parse_known_args(args=args)
 
 
-def main(args: Optional[Sequence[str]] = None) -> int:
+def main(args: Sequence[str] | None = None) -> int:
     """Provide the main entrypoint."""
     parsed_args, remainder_args = get_args(args=args)
     set_logger_level(parsed_args.verbose - parsed_args.quiet)
diff --git a/src/phylum/ci/common.py b/src/phylum/ci/common.py
index 61664e4..5c6e5c8 100644
--- a/src/phylum/ci/common.py
+++ b/src/phylum/ci/common.py
@@ -5,7 +5,6 @@
 import json
 import os
 from pathlib import Path
-from typing import Union
 
 
 @dataclasses.dataclass(order=True, frozen=True)
@@ -46,7 +45,7 @@ class DepfileEntry:
     Current commands that return entries in this format include `status --json` and `find-dependency-files`.
     """
 
-    path_: dataclasses.InitVar[Union[str, Path]]
+    path_: dataclasses.InitVar[str | Path]
     type: str = "auto"
     path: Path = dataclasses.field(init=False)
 
diff --git a/src/phylum/ci/depfile.py b/src/phylum/ci/depfile.py
index e29ecc0..6f18f20 100644
--- a/src/phylum/ci/depfile.py
+++ b/src/phylum/ci/depfile.py
@@ -13,7 +13,6 @@
 from pathlib import Path
 import shlex
 import subprocess
-from typing import Optional
 
 from phylum.ci.common import CLIExitCode, DepfileEntry, Package, Packages
 from phylum.exceptions import PhylumCalledProcessError
@@ -54,7 +53,7 @@ def __init__(
         self.cli_path = cli_path
         self._depfile_type = depfile_type
         self.disable_lockfile_generation = disable_lockfile_generation
-        self._is_depfile_changed: Optional[bool] = None
+        self._is_depfile_changed: bool | None = None
 
     def __repr__(self) -> str:
         """Return a debug printable string representation of the `Depfile` object."""
@@ -88,7 +87,7 @@ def type(self) -> str:
         return self._type
 
     @property
-    def is_depfile_changed(self) -> Optional[bool]:
+    def is_depfile_changed(self) -> bool | None:
         """Predicate for detecting if the dependency file has changed."""
         return self._is_depfile_changed
 
@@ -158,7 +157,7 @@ def parse_depfile(
     depfile_type: str,
     depfile_path: Path,
     *,
-    start: Optional[Path] = None,
+    start: Path | None = None,
     disable_lockfile_generation: bool = False,
 ) -> Packages:
     """Parse a dependency file and return its packages.
diff --git a/src/phylum/ci/git.py b/src/phylum/ci/git.py
index 9e203e4..65a5e8a 100644
--- a/src/phylum/ci/git.py
+++ b/src/phylum/ci/git.py
@@ -7,13 +7,12 @@
 import shlex
 import subprocess
 import tempfile
-from typing import Optional
 
 from phylum.exceptions import PhylumCalledProcessError, pprint_subprocess_error
 from phylum.logger import LOG, MARKUP
 
 
-def git_base_cmd(git_c_path: Optional[Path] = None) -> list[str]:
+def git_base_cmd(git_c_path: Path | None = None) -> list[str]:
     """Provide a normalized base command list for use in constructing git commands.
 
     The optional `git_c_path` is used to tell `git` to run as if it were started in that
@@ -24,7 +23,7 @@ def git_base_cmd(git_c_path: Optional[Path] = None) -> list[str]:
     return ["git", "-C", str(git_c_path.resolve())]
 
 
-def is_in_git_repo(git_c_path: Optional[Path] = None) -> bool:
+def is_in_git_repo(git_c_path: Path | None = None) -> bool:
     """Predicate for determining if operating within the context of an accessible git repository.
 
     The optional `git_c_path` is used to tell `git` to run as if it were started in that
@@ -37,7 +36,7 @@ def is_in_git_repo(git_c_path: Optional[Path] = None) -> bool:
     return not bool(subprocess.run(cmd, check=False, capture_output=True).returncode)  # noqa: S603
 
 
-def ensure_git_repo_access(git_c_path: Optional[Path] = None) -> None:
+def ensure_git_repo_access(git_c_path: Path | None = None) -> None:
     """Ensure user account executing `git` has access to the repository.
 
     The optional `git_c_path` is used to tell `git` to run as if it were started in that
@@ -104,7 +103,7 @@ def ensure_git_repo_access(git_c_path: Optional[Path] = None) -> None:
             LOG.warning(cleandoc(msg), extra=MARKUP)
 
 
-def git_remote(git_c_path: Optional[Path] = None) -> str:
+def git_remote(git_c_path: Path | None = None) -> str:
     """Get the git remote and return it.
 
     The optional `git_c_path` is used to tell `git` to run as if it were started in that
@@ -135,7 +134,7 @@ def git_remote(git_c_path: Optional[Path] = None) -> str:
     return remote
 
 
-def git_fetch(repo: Optional[str] = None, ref: Optional[str] = None, git_c_path: Optional[Path] = None) -> None:
+def git_fetch(repo: str | None = None, ref: str | None = None, git_c_path: Path | None = None) -> None:
     """Execute a `git fetch` command with optional repository and refspec specified.
 
     See git documentation for more detail: https://git-scm.com/docs/git-fetch
@@ -158,7 +157,7 @@ def git_fetch(repo: Optional[str] = None, ref: Optional[str] = None, git_c_path:
         raise PhylumCalledProcessError(err, msg) from err
 
 
-def git_branch_exists(ref_path: str, git_c_path: Optional[Path] = None) -> bool:
+def git_branch_exists(ref_path: str, git_c_path: Path | None = None) -> bool:
     """Predicate for whether a given branch exists.
 
     `ref_path` is meant to be an "exact path" to a specific reference (e.g., `refs/remotes/origin/main`)
@@ -178,7 +177,7 @@ def git_branch_exists(ref_path: str, git_c_path: Optional[Path] = None) -> bool:
     return True
 
 
-def git_set_remote_head(remote: str, git_c_path: Optional[Path] = None) -> None:
+def git_set_remote_head(remote: str, git_c_path: Path | None = None) -> None:
     """Set the remote HEAD ref for a given remote.
 
     The optional `git_c_path` is used to tell `git` to run as if it were started in that
@@ -197,7 +196,7 @@ def git_set_remote_head(remote: str, git_c_path: Optional[Path] = None) -> None:
         raise PhylumCalledProcessError(err, msg) from err
 
 
-def git_default_branch_name(remote: str, git_c_path: Optional[Path] = None) -> str:
+def git_default_branch_name(remote: str, git_c_path: Path | None = None) -> str:
     """Get the default branch name and return it.
 
     The optional `git_c_path` is used to tell `git` to run as if it were started in that
@@ -239,7 +238,7 @@ def git_default_branch_name(remote: str, git_c_path: Optional[Path] = None) -> s
     return default_branch_name
 
 
-def git_root_dir(git_c_path: Optional[Path] = None) -> Path:
+def git_root_dir(git_c_path: Path | None = None) -> Path:
     """Get the top-level (root) directory of the git working tree and return it.
 
     The optional `git_c_path` is used to tell `git` to run as if it were started in that
@@ -261,7 +260,7 @@ def git_root_dir(git_c_path: Optional[Path] = None) -> Path:
     return Path(git_root).resolve()
 
 
-def git_current_branch_name(git_c_path: Optional[Path] = None) -> str:
+def git_current_branch_name(git_c_path: Path | None = None) -> str:
     """Get the current branch name and return it.
 
     The optional `git_c_path` is used to tell `git` to run as if it were started in that
@@ -283,7 +282,7 @@ def git_current_branch_name(git_c_path: Optional[Path] = None) -> str:
     return current_branch
 
 
-def git_hash_object(object_path: Path, git_c_path: Optional[Path] = None) -> str:
+def git_hash_object(object_path: Path, git_c_path: Path | None = None) -> str:
     """Get the unique key that git uses to refer to the blob type data object for the provided path and return it.
 
     The optional `git_c_path` is used to tell `git` to run as if it were started in that
@@ -306,7 +305,7 @@ def git_hash_object(object_path: Path, git_c_path: Optional[Path] = None) -> str
     return hash_object
 
 
-def git_repo_name(git_c_path: Optional[Path] = None) -> str:
+def git_repo_name(git_c_path: Path | None = None) -> str:
     """Get the git repository name and return it.
 
     The optional `git_c_path` is used to tell `git` to run as if it were started in that
@@ -361,8 +360,8 @@ def git_repo_name(git_c_path: Optional[Path] = None) -> str:
 @contextlib.contextmanager
 def git_worktree(
     commit: str,
-    env: Optional[Mapping[str, str]] = None,
-    git_c_path: Optional[Path] = None,
+    env: Mapping[str, str] | None = None,
+    git_c_path: Path | None = None,
 ) -> Generator[Path, None, None]:
     """Create a git worktree at the given commit.
 
@@ -395,7 +394,7 @@ def git_worktree(
             remove_git_worktree(temp_dir_path)
 
 
-def remove_git_worktree(worktree: Path, git_c_path: Optional[Path] = None) -> None:
+def remove_git_worktree(worktree: Path, git_c_path: Path | None = None) -> None:
     """Remove a given git worktree.
 
     The optional `git_c_path` is used to tell `git` to run as if it were started in that
diff --git a/src/phylum/console.py b/src/phylum/console.py
index b095eb0..ad5e7f5 100644
--- a/src/phylum/console.py
+++ b/src/phylum/console.py
@@ -5,7 +5,6 @@
 """
 
 from collections.abc import Mapping
-from typing import Union
 
 from rich.console import Console
 from rich.style import Style
@@ -19,7 +18,7 @@
 # References:
 #   * https://rich.readthedocs.io/en/latest/style.html
 #   * https://rich.readthedocs.io/en/latest/appendix/colors.html
-PHYLUM_STYLES: Mapping[str, Union[str, Style]] = {
+PHYLUM_STYLES: Mapping[str, str | Style] = {
     # Styles that have been added to the default:
     "logging.level.trace": Style(dim=True),
     # Styles that have been modified from the default:
diff --git a/src/phylum/github.py b/src/phylum/github.py
index d1a2558..ab64bcb 100644
--- a/src/phylum/github.py
+++ b/src/phylum/github.py
@@ -3,7 +3,7 @@
 from inspect import cleandoc
 import os
 import time
-from typing import Any, Optional
+from typing import Any
 
 import requests
 
@@ -25,7 +25,7 @@
 PAT_REF = "https://docs.github.com/authentication/keeping-your-account-and-data-secure/creating-a-personal-access-token"
 
 
-def get_headers(github_token: Optional[str] = None) -> dict[str, str]:
+def get_headers(github_token: str | None = None) -> dict[str, str]:
     """Get the headers to use for a GitHub API request.
 
     Authenticated requests are made by providing a GitHub token. The token can be passed by parameter
@@ -50,8 +50,8 @@ def get_headers(github_token: Optional[str] = None) -> dict[str, str]:
 @progress_spinner("Making GitHub API request")
 def github_request(
     api_url: str,
-    params: Optional[dict] = None,
-    github_token: Optional[str] = None,
+    params: dict | None = None,
+    github_token: str | None = None,
     timeout: float = REQ_TIMEOUT,
 ) -> Any:
     """Make a request to a given GitHub API endpoint and return the response.
diff --git a/src/phylum/init/cli.py b/src/phylum/init/cli.py
index 885058c..73e9bd6 100644
--- a/src/phylum/init/cli.py
+++ b/src/phylum/init/cli.py
@@ -13,7 +13,6 @@
 import subprocess
 import sys
 import tempfile
-from typing import Optional
 import zipfile
 
 from packaging.utils import canonicalize_version
@@ -77,7 +76,7 @@ def get_phylum_cli_version(cli_path: Path) -> str:
     return version
 
 
-def get_phylum_bin_path() -> tuple[Optional[Path], Optional[str]]:
+def get_phylum_bin_path() -> tuple[Path | None, str | None]:
     """Get the current path and corresponding version to the Phylum CLI binary and return them."""
     # Look for `phylum` on the PATH first
     which_cli_path = shutil.which("phylum")
@@ -248,7 +247,7 @@ def version_check(version: str) -> str:
     return version
 
 
-def process_version(version: Optional[str]) -> str:
+def process_version(version: str | None) -> str:
     """Process the version argument and return it.
 
     Avoid external GitHub API calls when an existing Phylum CLI is installed and it's version is supported.
@@ -298,7 +297,7 @@ def get_archive_url(tag_name: str, archive_name: str) -> str:
     return archive_url
 
 
-def is_token_set(phylum_settings_path: Path, token: Optional[str] = None) -> bool:
+def is_token_set(phylum_settings_path: Path, token: str | None = None) -> bool:
     """Check if any token is already set in the given CLI configuration file.
 
     Optionally, check if a specific given `token` is set.
@@ -562,7 +561,7 @@ def confirm_setup() -> None:
     LOG.debug(help_output)
 
 
-def get_args(args: Optional[Sequence[str]] = None) -> argparse.Namespace:
+def get_args(args: Sequence[str] | None = None) -> argparse.Namespace:
     """Get the arguments from the command line or input parameter, parse and return them."""
     parser = argparse.ArgumentParser(
         prog=SCRIPT_NAME,
@@ -642,7 +641,7 @@ def get_args(args: Optional[Sequence[str]] = None) -> argparse.Namespace:
     return parser.parse_args(args=args)
 
 
-def main(args: Optional[Sequence[str]] = None) -> int:
+def main(args: Sequence[str] | None = None) -> int:
     """Provide the main entrypoint."""
     parsed_args = get_args(args=args)
     set_logger_level(parsed_args.verbose - parsed_args.quiet)
diff --git a/src/phylum/logger.py b/src/phylum/logger.py
index bd81362..746ed17 100644
--- a/src/phylum/logger.py
+++ b/src/phylum/logger.py
@@ -1,10 +1,11 @@
 """Configure the logging features for the package."""
 
+from collections.abc import Callable
 import inspect
 import logging
 import sys
 from types import FunctionType, MethodType
-from typing import Any, Callable, Optional
+from typing import Any
 
 from rich.logging import RichHandler
 from rich.progress import Progress, SpinnerColumn, TextColumn, TimeElapsedColumn
@@ -41,7 +42,7 @@
 #  * https://stackoverflow.com/a/35804945
 #  * https://github.com/python/cpython/issues/75913#issuecomment-1093761548
 #  * https://github.com/madphysicist/haggis/blob/master/src/haggis/logs.py
-def add_logging_level(level_name: str, level_num: int, method_name: Optional[str] = None) -> None:
+def add_logging_level(level_name: str, level_num: int, method_name: str | None = None) -> None:
     """Add a new logging level to the `logging` module and the currently configured logging class.
 
     `level_name` becomes an attribute of the `logging` module with the value `level_num`.
diff --git a/tests/unit/test_package_metadata.py b/tests/unit/test_package_metadata.py
index 987760e..8d61c34 100644
--- a/tests/unit/test_package_metadata.py
+++ b/tests/unit/test_package_metadata.py
@@ -18,7 +18,7 @@ def test_project_version():
 
 def test_python_version():
     """Ensure the python version used to test is a supported version."""
-    supported_minor_versions = (9, 10, 11, 12)
+    supported_minor_versions = (10, 11, 12, 13)
     python_version = sys.version_info
     acceptable_python_major_version = 3
     assert python_version.major == acceptable_python_major_version, "Only Python 3 is supported"
diff --git a/tox.ini b/tox.ini
index 3852d47..4e50d42 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,15 +1,15 @@
 [tox]
 # Sub-commands were introduced in v4. These are used in workflows and docs.
 min_version = 4
-envlist = py39, py310, py311, py312
+envlist = py310, py311, py312, py313
 isolated_build = true
 
 [gh-actions]
 python =
-    3.9: py39
     3.10: py310
     3.11: py311
     3.12: py312
+    3.13: py313
 
 [testenv]
 description = Test environment for minor Python version