Raise minimum supported Python version to 3.11

.github/workflows/docs.yml

@@ -26,7 +26,7 @@ jobs:
           submodules: recursive
       - uses: actions/setup-python@v7
         with:
-          python-version: '3.10'
+          python-version: '3.11'
       - name: Install dependencies
         # autodoc imports the package, so the extension has to compile here -- hence the
         # same MPI and BLAS packages the test workflow installs, rather than the lighter

.github/workflows/test_development_versions.yml

@@ -22,7 +22,7 @@ jobs:
       max-parallel: 4
       matrix:
         os: [ubuntu-latest]
-        python-version: ["3.10", "3.14"]
+        python-version: ["3.11", "3.14"]
     steps:
       - uses: actions/checkout@v7
         with:

.github/workflows/test_latest_versions.yml

@@ -24,7 +24,7 @@ jobs:
       max-parallel: 4
       matrix:
         os: [ubuntu-latest, macos-latest]
-        python-version: ["3.10", "3.11", "3.12", "3.13", "3.14"]
+        python-version: ["3.11", "3.12", "3.13", "3.14"]
     steps:
       - uses: actions/checkout@v7
         with:

.github/workflows/test_minimum_versions.yml

@@ -20,7 +20,7 @@ jobs:
       max-parallel: 4
       matrix:
         os: [ubuntu-latest]
-        python-version: ["3.10"]
+        python-version: ["3.11"]
     steps:
       - uses: actions/checkout@v7
         with:

INSTALL.md

@@ -8,7 +8,7 @@ reads, building against a host MPI, and how to verify what you got.
 
 ## Prerequisites
 
-**Required:** Python 3.10+, MPI (OpenMPI/MPICH), BLAS (OpenBLAS/MKL), pybind11, mpi4py, numpy, compiler with OpenMP.
+**Required:** Python 3.11+, MPI (OpenMPI/MPICH), BLAS (OpenBLAS/MKL), pybind11, mpi4py, numpy, compiler with OpenMP.
 
 **On macOS:** Apple clang ships without OpenMP, so add `llvm-openmp` to the conda
 environment. Homebrew's `libomp` is used as a fallback if the env has none. Pin the

pyproject.toml

@@ -7,7 +7,7 @@ name = "sbd-eigensolver"
 version = "1.7.0"
 description = "Python bindings for Selected Basis Diagonalization (SBD) library"
 readme = "README.md"
-requires-python = ">=3.10"
+requires-python = ">=3.11"
 license = "Apache-2.0"
 license-files = ["LICENSE.txt"]
 keywords = ["quantum chemistry", "diagonalization", "tensor product basis", "MPI"]
@@ -19,7 +19,6 @@ classifiers = [
     "Topic :: Scientific/Engineering :: Chemistry",
     "Topic :: Scientific/Engineering :: Physics",
     "Programming Language :: Python :: 3",
-    "Programming Language :: Python :: 3.10",
     "Programming Language :: Python :: 3.11",
     "Programming Language :: Python :: 3.12",
     "Programming Language :: Python :: 3.13",

releasenotes/notes/bump-minimum-python-38a75964047ebb47.yaml

@@ -0,0 +1,6 @@
+---
+upgrade:
+  - |
+    Support for Python 3.10 has been dropped.  Python 3.11 or later is now
+    required.  Python 3.10 reached `end of life <https://devguide.python.org/versions/>`__
+    on October 1, 2026.

tox.ini

@@ -1,6 +1,6 @@
 [tox]
-minversion = 4.4.3
-envlist = py{310,311,312,313,314}{,-notebook}, mpi, docs
+minversion = 4.4.4
+envlist = py{311,312,313,314}{,-notebook}, mpi, docs
 isolated_build = True
 
 [testenv]
@@ -78,12 +78,12 @@ commands =
     mpirun -n {env:SBD_TEST_NPROCS} pytest --only-mpi {posargs}
 
 # Spelled out with the hyphen outside the braces. Writing this as
-# {,py310-,py311-,...}notebook does not work: tox expands numeric ranges in a section
+# {,py311-,py312-,...}notebook does not work: tox expands numeric ranges in a section
 # name before splitting it on braces, so `py314-` parses as `py3` plus the range `14-`,
-# which produces junk environment names and never defines py310-notebook and friends --
+# which produces junk environment names and never defines py311-notebook and friends --
 # those then silently fall through to [testenv] and run the unit tests instead. Nesting
 # braces is not an alternative either; it crashes tox outright.
-[testenv:{notebook,py310-notebook,py311-notebook,py312-notebook,py313-notebook,py314-notebook}]
+[testenv:{notebook,py311-notebook,py312-notebook,py313-notebook,py314-notebook}]
 # nbmake runs each notebook with its own directory as the working directory, so the
 # relative paths the examples use to reach the vendored data resolve as they would for
 # someone running the notebook by hand.