Allow nanobind 3.0.x and drop support for Python 3.9

[rmisev]

nanobind 3.0.0 requires Python 3.10 or newer. See: https://nanobind.readthedocs.io/en/latest/changelog.html#version-3-0-0-aug-22-2026

[Copilot]

🟢 Approval recommended

The Python version floor and nanobind constraints are updated consistently across packaging, build configuration, and CI, with no remaining Python 3.9 references found.

Pull request overview

This PR updates the project’s declared Python support to align with nanobind 3.0.0’s requirement of Python 3.10+ and relaxes the nanobind upper bound to allow 3.0.x.

Changes:

• Expand the build-system nanobind constraint to allow nanobind 3.0.x (<3.1.0).
• Drop Python 3.9 support by raising requires-python to >=3.10.
• Update CMake and GitHub Actions test matrix to use Python 3.10+ (removing 3.9).

File summaries

File	Description
pyproject.toml	Raises requires-python to 3.10+ and allows nanobind 3.0.x via updated version constraint.
CMakeLists.txt	Updates find_package(Python ...) minimum version to 3.10 to match supported Python floor.
.github/workflows/test.yml	Removes Python 3.9 from the CI test matrix and adds Python 3.10.

Review details

• Files reviewed: 3/3 changed files
• Comments generated: 0
• Review effort level: Lite

---

💡 Add a code-review agent skill or configure MCP servers for context-aware, tailored reviews. Learn more in the docs.