diff --git a/.github/workflows/python-package.yml b/.github/workflows/python-package.yml
index e851aeac1..2c24efa9c 100644
--- a/.github/workflows/python-package.yml
+++ b/.github/workflows/python-package.yml
@@ -68,7 +68,7 @@ jobs:
         with:
           token: ${{ secrets.CODECOV_TOKEN }}
   test-pypy:
-    name: 'Python pypy3.9/Cython: false'
+    name: 'Python pypy3.11/Cython: false'
     runs-on: ubuntu-latest
     timeout-minutes: 10
     continue-on-error: true
@@ -80,7 +80,7 @@ jobs:
           fetch-depth: 0
       - uses: actions/setup-python@v5
         with:
-          python-version: pypy3.9
+          python-version: pypy3.11
           cache: pip
           cache-dependency-path: requirements/test.txt
       - name: Install dependencies
@@ -183,13 +183,17 @@ jobs:
     if: github.event_name == 'release' && github.event.action == 'created'
     strategy:
       matrix:
-        os: [ubuntu-20.04, macos-13, macos-14]
+        # Modern, supported runner images (ubuntu-20.04 was retired in 2025).
+        # macos-15-intel -> x86_64 wheels, macos-14 -> arm64 wheels,
+        # windows-2022 -> AMD64 wheels. Build config lives in
+        # pyproject.toml's [tool.cibuildwheel] (cp3*, auto64, Cython).
+        os: [ubuntu-latest, macos-15-intel, macos-14, windows-2022]
     steps:
       - uses: actions/checkout@v4
         with:
           fetch-depth: 0
       - name: Build wheels
-        uses: pypa/cibuildwheel@v2.10.1
+        uses: pypa/cibuildwheel@v2.21.3
       - uses: actions/upload-artifact@v4
         with:
           name: cibw-wheels-${{ matrix.os }}
diff --git a/pyproject.toml b/pyproject.toml
index b4b7f923c..23afb32fb 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -29,6 +29,8 @@ classifiers = [
     "Programming Language :: Python :: 3.10",
     "Programming Language :: Python :: 3.11",
     "Programming Language :: Python :: 3.12",
+    "Programming Language :: Python :: 3.13",
+    "Programming Language :: Python :: 3.14",
     "Programming Language :: Python :: Implementation :: CPython",
     "Operating System :: POSIX",
     "Operating System :: POSIX :: Linux",
diff --git a/requirements/test.txt b/requirements/test.txt
index 832762190..759f5bd62 100644
--- a/requirements/test.txt
+++ b/requirements/test.txt
@@ -1,13 +1,9 @@
 # Formatters are pinned so `scripts/check` is reproducible: new releases
 # change formatting output and would fail lint on an otherwise-unchanged
 # tree. They are lint-only tools, run only by the lint job (PYTHON_LATEST).
-# The current pins require Python >= 3.10, so guard them with a marker and
-# fall back to an unpinned install on 3.9 (installed there but never run).
 # Bump the pins deliberately, together with a tree-wide reformat.
-black==26.5.1; python_version >= "3.10"
-black; python_version < "3.10"
-isort==8.0.1; python_version >= "3.10"
-isort; python_version < "3.10"
+black==26.5.1
+isort==8.0.1
 autoflake
 flake8==5.0.4  # 5.0.4 can be upgraded to 6.0.0+ when we EOL Python 3.7
 flake8-bugbear