From 70d31a3e25326a704fcef4f8eb5644010603ccea Mon Sep 17 00:00:00 2001
From: Jammy2211 <JNightingale2211@gmail.com>
Date: Wed, 29 Jul 2026 10:47:20 +0100
Subject: [PATCH] feat: require Python 3.12

---
 AGENTS.md                                    |  2 +-
 autofit/graphical/factor_graphs/abstract.py  |  3 +--
 autofit/graphical/factor_graphs/jacobians.py |  4 +---
 pyproject.toml                               | 15 +++------------
 4 files changed, 6 insertions(+), 18 deletions(-)

diff --git a/AGENTS.md b/AGENTS.md
index 2d20d118c..c21599567 100644
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -43,7 +43,7 @@ NUMBA_CACHE_DIR=/tmp/numba_cache MPLCONFIGDIR=/tmp/matplotlib python -m pytest t
 
 PRs must pass `pytest --cov` on the CI matrix (Python 3.12 **and** 3.13). There
 is no black/ruff/flake8 gate — formatting is advisory. (`requires-python` in
-`pyproject.toml` is `>=3.9`.)
+`pyproject.toml` is `>=3.12`.)
 
 ## Configuration & defaults
 
diff --git a/autofit/graphical/factor_graphs/abstract.py b/autofit/graphical/factor_graphs/abstract.py
index 91313813f..55dab4279 100644
--- a/autofit/graphical/factor_graphs/abstract.py
+++ b/autofit/graphical/factor_graphs/abstract.py
@@ -8,6 +8,7 @@
     Optional,
     Collection,
     Any,
+    Protocol,
     TYPE_CHECKING, 
 )
 
@@ -36,8 +37,6 @@
     from autofit.graphical.mean_field import MeanField
     from autofit.graphical.expectation_propagation import EPMeanField
 
-Protocol = ABC  # for python 3.7 compat
-
 Value = Dict[Variable, np.ndarray]
 
 GradientValue = VariableData
diff --git a/autofit/graphical/factor_graphs/jacobians.py b/autofit/graphical/factor_graphs/jacobians.py
index 0385b559d..447b36402 100644
--- a/autofit/graphical/factor_graphs/jacobians.py
+++ b/autofit/graphical/factor_graphs/jacobians.py
@@ -16,16 +16,14 @@
 from autofit.mapper.variable_operator import (
     RectVariableOperator,
 )
-from abc import ABC
 from typing import (
     Tuple,
     Dict,
     Union,
     Callable,
+    Protocol,
 )
 
-Protocol = ABC  # for python 3.7 compat
-
 Value = Dict[Variable, np.ndarray]
 GradientValue = VariableData
 
diff --git a/pyproject.toml b/pyproject.toml
index 4a681cd35..1fc09840f 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -8,7 +8,7 @@ dynamic = ["version"]
 description = "Classy Probabilistic Programming"
 readme = { file = "README.md", content-type = "text/markdown" }
 license = { text = "MIT" }
-requires-python = ">=3.9"
+requires-python = ">=3.12"
 authors = [
     { name = "James Nightingale", email = "James.Nightingale@newcastle.ac.uk" },
     { name = "Richard Hayes", email = "richard@rghsoftware.co.uk" },
@@ -18,9 +18,6 @@ classifiers = [
   "Topic :: Scientific/Engineering :: Physics",
   "Natural Language :: English",
   "Operating System :: OS Independent",
-  "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"
 ]
@@ -66,13 +63,7 @@ local_scheme = "no-local-version"
 
 
 [project.optional-dependencies]
-# optax carries the same `python_version >= '3.11'` marker every entry in
-# autonerves[jax] does. Without it, resolving this extra on 3.9/3.10 sends pip
-# backtracking through the whole optax/jax release history looking for a version
-# with wheels for that interpreter — which ends in `resolution-too-deep`, taking
-# every 3.9 leg of python_matrix red. optax is only useful where jax is
-# installed, and jax is gated to 3.11+, so gating optax to match loses nothing.
-jax = ["autonerves[jax]", "optax>=0.2.5; python_version >= '3.11'"]
+jax = ["autonerves[jax]", "optax>=0.2.5"]
 mcp = ["mcp"]
 optional = [
     "autofit[jax]",
@@ -104,4 +95,4 @@ filterwarnings = [
     "ignore:cuda_plugin_extension:UserWarning",
     "ignore::DeprecationWarning:jax",
     "ignore:relationship .* will copy column:sqlalchemy.exc.SAWarning",
-]
\ No newline at end of file
+]