diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index b62c806a..228f2e6e 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -32,7 +32,7 @@ jobs:
       - name: Setup python
         uses: actions/setup-python@v5.2.0
         with:
-          python-version: "3.12"
+          python-version: "3.13"
       - name: Install requirements
         run: |
           python -m pip install -U pip
@@ -53,7 +53,7 @@ jobs:
         with:
           cache: pip
           cache-dependency-path: requirements/lint.txt
-          python-version: "3.12"
+          python-version: "3.13"
       - name: Install requirements
         run: |
           python -m pip install -U pip
@@ -125,9 +125,6 @@ jobs:
 #            python: '3.13-dev'
 #            experimental: true
 #            test-timeout: 3
-        exclude:
-          - os: macos-latest
-            python: '3.8'
     steps:
       - name: Input settings
         run: echo "${{ needs.Build.outputs.settings }}" | base64 -d | tar xz
@@ -180,7 +177,7 @@ jobs:
           - ubuntu-latest
           - macos-latest
         python:
-          - '3.12'
+          - '3.13'
           - 'pypy-3.10'
     steps:
       - name: Checkout
@@ -211,7 +208,7 @@ jobs:
       - name: Setup python
         uses: actions/setup-python@v5.2.0
         with:
-          python-version: '3.12'
+          python-version: '3.13'
       - name: Download build artifact
         uses: actions/download-artifact@v4.1.2
         with:
@@ -243,7 +240,7 @@ jobs:
         with:
           cache: pip
           cache-dependency-path: requirements/coverage.txt
-          python-version: "3.12"
+          python-version: "3.13"
       - name: Install coverage
         run: |
           pip install -U pip
diff --git a/.readthedocs.yml b/.readthedocs.yml
index c5108e35..79d6a52d 100644
--- a/.readthedocs.yml
+++ b/.readthedocs.yml
@@ -2,9 +2,9 @@
 version: 2
 
 build:
-  os: ubuntu-20.04
+  os: ubuntu-22.04
   tools:
-    python: "3.10"
+    python: "3.12"
   jobs:
     post_checkout:
       - git fetch --unshallow
diff --git a/codecov.yml b/codecov.yml
deleted file mode 100644
index 3c4e1438..00000000
--- a/codecov.yml
+++ /dev/null
@@ -1,8 +0,0 @@
-# https://docs.codecov.io/docs/codecovyml-reference
-
-coverage:
-  precision: 1
-  round: down
-  range: "70...100"
-
-comment: false
diff --git a/docs/source/conf.py b/docs/source/conf.py
index 97799dbb..051e1395 100644
--- a/docs/source/conf.py
+++ b/docs/source/conf.py
@@ -19,8 +19,9 @@
 #
 import os
 import sys
+
 # So autodoc can import our package
-sys.path.insert(0, os.path.abspath('../..'))
+sys.path.insert(0, os.path.abspath("../.."))
 
 
 # Warn about all references to unknown targets
@@ -57,17 +58,17 @@
 # extensions coming with Sphinx (named 'sphinx.ext.*') or your custom
 # ones.
 extensions = [
-    'sphinx.ext.autodoc',
-    'sphinx.ext.intersphinx',
-    'sphinx.ext.coverage',
-    'sphinx.ext.napoleon',
-    'sphinxcontrib_trio',
-    'sphinxcontrib.jquery',
+    "sphinx.ext.autodoc",
+    "sphinx.ext.intersphinx",
+    "sphinx.ext.coverage",
+    "sphinx.ext.napoleon",
+    "sphinxcontrib_trio",
+    "sphinxcontrib.jquery",
 ]
 
 intersphinx_mapping = {
-    "python": ('https://docs.python.org/3', None),
-    "trio": ('https://trio.readthedocs.io/en/stable', None),
+    "python": ("https://docs.python.org/3", None),
+    "trio": ("https://trio.readthedocs.io/en/stable", None),
 }
 
 autodoc_member_order = "bysource"
@@ -79,15 +80,15 @@
 # You can specify multiple suffix as a list of string:
 #
 # source_suffix = ['.rst', '.md']
-source_suffix = '.rst'
+source_suffix = ".rst"
 
 # The master toctree document.
-master_doc = 'index'
+master_doc = "index"
 
 # General information about the project.
-project = 'trio-parallel'
-copyright = 'Richard J. Sheridan'
-author = 'Richard J. Sheridan'
+project = "trio-parallel"
+copyright = "Richard J. Sheridan"
+author = "Richard J. Sheridan"
 
 # The version info for the project you're documenting, acts as replacement for
 # |version| and |release|, also used in various other places throughout the
@@ -95,16 +96,19 @@
 #
 # The short X.Y version.
 from importlib.metadata import version
-version = version('trio-parallel')
+
+version = version("trio-parallel")
 # The full version, including alpha/beta/rc tags.
 release = version
 
 # https://docs.readthedocs.io/en/stable/builds.html#build-environment
 if "READTHEDOCS" in os.environ:
     import glob
+
     if glob.glob("../../newsfragments/*.*.rst"):
         print("-- Found newsfragments; running towncrier --", flush=True)
         import subprocess
+
         subprocess.run(
             ["towncrier", "build", "--yes", "--version", version],
             cwd="../..",
@@ -120,7 +124,7 @@
 #
 # This is also used if you do content translation via gettext catalogs.
 # Usually you set "language" from the command line for these cases.
-language = 'en'
+language = "en"
 
 # List of patterns, relative to source directory, that match files and
 # directories to ignore when looking for source files.
@@ -128,10 +132,10 @@
 exclude_patterns = []
 
 # The name of the Pygments (syntax highlighting) style to use.
-pygments_style = 'sphinx'
+pygments_style = "sphinx"
 
 # The default language for :: blocks
-highlight_language = 'python3'
+highlight_language = "python3"
 
 # If true, `todo` and `todoList` produce output, else they produce nothing.
 todo_include_todos = False
@@ -150,14 +154,12 @@
 # The theme to use for HTML and HTML Help pages.  See the documentation for
 # a list of builtin themes.
 #
-#html_theme = 'alabaster'
+# html_theme = 'alabaster'
 
 # We have to set this ourselves, not only because it's useful for local
 # testing, but also because if we don't then RTD will throw away our
 # html_theme_options.
-import sphinx_rtd_theme
-html_theme = 'sphinx_rtd_theme'
-html_theme_path = [sphinx_rtd_theme.get_html_theme_path()]
+html_theme = "sphinx_rtd_theme"
 
 # Theme options are theme-specific and customize the look and feel of a theme
 # further.  For a list of options available for each theme, see the
@@ -171,22 +173,22 @@
     # versions/settings...
     "navigation_depth": 4,
     "logo_only": True,
-    'prev_next_buttons_location': 'both'
+    "prev_next_buttons_location": "both",
 }
 
 # Add any paths that contain custom static files (such as style sheets) here,
 # relative to this directory. They are copied after the builtin static files,
 # so a file named "default.css" will overwrite the builtin "default.css".
-html_static_path = ['_static']
+html_static_path = ["_static"]
 
 html_css_files = [
-    'custom.css',
+    "custom.css",
 ]
 
 # -- Options for HTMLHelp output ------------------------------------------
 
 # Output file base name for HTML help builder.
-htmlhelp_basename = 'trio-paralleldoc'
+htmlhelp_basename = "trio-paralleldoc"
 
 
 # -- Options for LaTeX output ---------------------------------------------
@@ -195,15 +197,12 @@
     # The paper size ('letterpaper' or 'a4paper').
     #
     # 'papersize': 'letterpaper',
-
     # The font size ('10pt', '11pt' or '12pt').
     #
     # 'pointsize': '10pt',
-
     # Additional stuff for the LaTeX preamble.
     #
     # 'preamble': '',
-
     # Latex figure (float) alignment
     #
     # 'figure_align': 'htbp',
@@ -213,8 +212,7 @@
 # (source start file, target name, title,
 #  author, documentclass [howto, manual, or own class]).
 latex_documents = [
-    (master_doc, 'trio-parallel.tex', 'Trio Documentation',
-     author, 'manual'),
+    (master_doc, "trio-parallel.tex", "Trio Documentation", author, "manual"),
 ]
 
 
@@ -222,10 +220,7 @@
 
 # One entry per manual page. List of tuples
 # (source start file, name, description, authors, manual section).
-man_pages = [
-    (master_doc, 'trio-parallel', 'trio-parallel Documentation',
-     [author], 1)
-]
+man_pages = [(master_doc, "trio-parallel", "trio-parallel Documentation", [author], 1)]
 
 
 # -- Options for Texinfo output -------------------------------------------
@@ -234,7 +229,13 @@
 # (source start file, target name, title, author,
 #  dir menu entry, description, category)
 texinfo_documents = [
-    (master_doc, 'trio-parallel', 'trio-parallel Documentation',
-     author, 'trio-parallel', 'CPU parallelism for Trio',
-     'Miscellaneous'),
+    (
+        master_doc,
+        "trio-parallel",
+        "trio-parallel Documentation",
+        author,
+        "trio-parallel",
+        "CPU parallelism for Trio",
+        "Miscellaneous",
+    ),
 ]
diff --git a/newsfragments/434.feature.rst b/newsfragments/434.feature.rst
new file mode 100644
index 00000000..3a5e670b
--- /dev/null
+++ b/newsfragments/434.feature.rst
@@ -0,0 +1 @@
+Advertise support for Python-3.13, although no code changes were made to support it.
diff --git a/newsfragments/434.removal.rst b/newsfragments/434.removal.rst
new file mode 100644
index 00000000..d015f9c1
--- /dev/null
+++ b/newsfragments/434.removal.rst
@@ -0,0 +1 @@
+Stop advertising support for Python-3.8, although no code changes were made to break it.
diff --git a/pyproject.toml b/pyproject.toml
index 0f41f8db..0ce7b807 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -18,11 +18,11 @@ classifiers = [
     "Operating System :: MacOS :: MacOS X",
     "Operating System :: Microsoft :: Windows",
     "Programming Language :: Python :: 3 :: Only",
-    "Programming Language :: Python :: 3.8",
     "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 :: Implementation :: CPython",
     "Programming Language :: Python :: Implementation :: PyPy",
     "Development Status :: 5 - Production/Stable",
diff --git a/requirements/coverage.txt b/requirements/coverage.txt
index c570a12e..d361c9d3 100644
--- a/requirements/coverage.txt
+++ b/requirements/coverage.txt
@@ -5,5 +5,5 @@
 #
 #    pip-compile-multi
 #
-coverage[toml]==7.5.4
+coverage[toml]==7.6.3
     # via -r requirements\coverage.in
diff --git a/requirements/dev.in b/requirements/dev.in
index 0f4d25cf..d9eb7a71 100644
--- a/requirements/dev.in
+++ b/requirements/dev.in
@@ -1,3 +1,4 @@
 -r test.in
 -r docs.in
--r lint.in
\ No newline at end of file
+-r lint.in
+-r coverage.in
diff --git a/requirements/dev.txt b/requirements/dev.txt
index 2b34fc7a..5b1bd822 100644
--- a/requirements/dev.txt
+++ b/requirements/dev.txt
@@ -1,10 +1,11 @@
-# SHA1:657999018ebf5f3362ebb8566642201085ff09d3
+# SHA1:64f3330cb21a24de944be0c0611a2d1920d63b44
 #
 # This file is autogenerated by pip-compile-multi
 # To update, run:
 #
 #    pip-compile-multi
 #
+-r coverage.txt
 -r docs.txt
 -r lint.txt
 -r test.txt
diff --git a/requirements/docs.txt b/requirements/docs.txt
index 21726a9a..4d33e1d8 100644
--- a/requirements/docs.txt
+++ b/requirements/docs.txt
@@ -6,13 +6,13 @@
 #    pip-compile-multi
 #
 -r install.txt
-alabaster==0.7.16
+alabaster==1.0.0
     # via sphinx
-babel==2.15.0
+babel==2.16.0
     # via sphinx
-certifi==2024.7.4
+certifi==2024.8.30
     # via requests
-charset-normalizer==3.3.2
+charset-normalizer==3.4.0
     # via requests
 click==8.1.7
     # via towncrier
@@ -20,19 +20,17 @@ colorama==0.4.6
     # via
     #   click
     #   sphinx
-docutils==0.20.1
+docutils==0.21.2
     # via
     #   sphinx
     #   sphinx-rtd-theme
 imagesize==1.4.1
     # via sphinx
-incremental==22.10.0
-    # via towncrier
 jinja2==3.1.4
     # via
     #   sphinx
     #   towncrier
-markupsafe==2.1.5
+markupsafe==3.0.2
     # via jinja2
 packaging==24.1
     # via sphinx
@@ -42,31 +40,31 @@ requests==2.32.3
     # via sphinx
 snowballstemmer==2.2.0
     # via sphinx
-sphinx==7.3.7
+sphinx==8.1.3
     # via
     #   -r requirements\docs.in
     #   sphinx-rtd-theme
     #   sphinxcontrib-jquery
     #   sphinxcontrib-trio
-sphinx-rtd-theme==2.0.0
+sphinx-rtd-theme==3.0.1
     # via -r requirements\docs.in
-sphinxcontrib-applehelp==1.0.8
+sphinxcontrib-applehelp==2.0.0
     # via sphinx
-sphinxcontrib-devhelp==1.0.6
+sphinxcontrib-devhelp==2.0.0
     # via sphinx
-sphinxcontrib-htmlhelp==2.0.5
+sphinxcontrib-htmlhelp==2.1.0
     # via sphinx
 sphinxcontrib-jquery==4.1
     # via sphinx-rtd-theme
 sphinxcontrib-jsmath==1.0.1
     # via sphinx
-sphinxcontrib-qthelp==1.0.7
+sphinxcontrib-qthelp==2.0.0
     # via sphinx
-sphinxcontrib-serializinghtml==1.1.10
+sphinxcontrib-serializinghtml==2.0.0
     # via sphinx
 sphinxcontrib-trio==1.1.2
     # via -r requirements\docs.in
-towncrier==23.11.0
+towncrier==24.8.0
     # via -r requirements\docs.in
-urllib3==2.2.2
+urllib3==2.2.3
     # via requests
diff --git a/requirements/install.txt b/requirements/install.txt
index 7e6ef4d5..8ffed149 100644
--- a/requirements/install.txt
+++ b/requirements/install.txt
@@ -5,16 +5,16 @@
 #
 #    pip-compile-multi
 #
-attrs==23.2.0
+attrs==24.2.0
     # via
     #   -r requirements\install.in
     #   outcome
     #   trio
-cffi==1.16.0 ; os_name == "nt" and implementation_name != "pypy"
+cffi==1.17.1 ; os_name == "nt" and implementation_name != "pypy"
     # via
     #   -r requirements\install.in
     #   trio
-idna==3.7
+idna==3.10
     # via trio
 outcome==1.3.0.post0
     # via
diff --git a/requirements/lint.txt b/requirements/lint.txt
index e91f9a85..7a6cb3b1 100644
--- a/requirements/lint.txt
+++ b/requirements/lint.txt
@@ -5,19 +5,19 @@
 #
 #    pip-compile-multi
 #
-black==24.4.2
+black==24.10.0
     # via -r requirements\lint.in
 click==8.1.7
     # via black
 colorama==0.4.6
     # via click
-flake8==7.1.0
+flake8==7.1.1
     # via
     #   -r requirements\lint.in
     #   flake8-async
-flake8-async==24.6.1
+flake8-async==24.9.5
     # via -r requirements\lint.in
-libcst==1.4.0
+libcst==1.5.0
     # via flake8-async
 mccabe==0.7.0
     # via flake8
@@ -27,11 +27,11 @@ packaging==24.1
     # via black
 pathspec==0.12.1
     # via black
-platformdirs==4.2.2
+platformdirs==4.3.6
     # via black
-pycodestyle==2.12.0
+pycodestyle==2.12.1
     # via flake8
 pyflakes==3.2.0
     # via flake8
-pyyaml==6.0.1
+pyyaml==6.0.2
     # via libcst
diff --git a/requirements/test.txt b/requirements/test.txt
index f57ab62b..da91ad80 100644
--- a/requirements/test.txt
+++ b/requirements/test.txt
@@ -8,7 +8,7 @@
 -r install.txt
 colorama==0.4.6
     # via pytest
-coverage[toml]==7.5.4
+coverage[toml]==7.6.3
     # via
     #   -r requirements\test.in
     #   pytest-cov
@@ -20,7 +20,7 @@ packaging==24.1
     # via pytest
 pluggy==1.5.0
     # via pytest
-pytest==8.2.2
+pytest==8.3.3
     # via
     #   -r requirements\test.in
     #   pytest-cov