diff --git a/pyproject.toml b/pyproject.toml
index cdf8a0e..5b27d52 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -79,7 +79,17 @@ max-complexity = 10
 
 # --- Types ------------------------------------------------------------------
 [tool.mypy]
-python_version = "3.10"
+# Deliberately NOT the minimum supported version. python_version is the syntax
+# level mypy parses *everything* with, dependency stubs included, and numpy's
+# stubs use PEP 695 `type` statements that only parse as 3.12+ -- with 3.10 here
+# mypy fails inside numpy before it reaches our code. Pinning it rather than
+# letting it follow the interpreter keeps mypy working on a 3.10 or 3.11 machine
+# too.
+#
+# The 3.10 floor is still enforced, just not here: ruff takes its target version
+# from requires-python and rejects newer syntax outright, and the test matrix
+# runs on 3.10.
+python_version = "3.12"
 files = ["src/garg_aml"]
 disallow_untyped_defs = true
 warn_redundant_casts = true