Drop Python 3.9 support

Python 3.9 reached end of life in October 2025; remove it from the CI matrix, classifiers, python_requires, and ruff target. Bump pypy-3.9 to pypy-3.10 in the matrix.

Author: bdraco

.github/workflows/ci-cd.yml

@@ -181,7 +181,6 @@ jobs:
         - 3.12
         - 3.11
         - "3.10"
-        - 3.9
         no-extensions: ['', 'Y']
         os: [ubuntu, macos, windows]
         debug: ['', 'Y']
@@ -199,7 +198,7 @@ jobs:
         - no-extensions: Y
           debug: Y
         include:
-        - pyver: pypy-3.9
+        - pyver: pypy-3.10
           no-extensions: Y
           os: ubuntu
           debug: ''

pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "setuptools.build_meta"
 
 
 [tool.ruff]
-target-version = "py39"
+target-version = "py310"
 
 [tool.cibuildwheel]
 test-requires = "-r requirements/pytest.txt"

setup.cfg

@@ -32,15 +32,14 @@ classifiers =
 
   Programming Language :: Python
   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
   Programming Language :: Python :: 3.14
 
 [options]
-python_requires = >= 3.9
+python_requires = >= 3.10
 install_requires =
   typing-extensions >= 4.1.0; python_version < '3.11'
 packages =