Below is guidance for building the DOLFINx Python interface.

1. Build and install the DOLFINx C++ library.

2. Ensure the Python interface build requirements are installed:

   pip install --group pyproject.toml:build
   

3. Build DOLFINx Python interface:

   pip install --check-build-dependencies --no-build-isolation .
   

To build in Developer and editable mode for development:

 pip -v install --check-build-dependencies -Cbuild-dir="build" -Ccmake.build-type="Developer" -Cinstall.strip=false --no-build-isolation -e .

Note that Developer mode is significantly stricter than CMake's default Debug mode.

1. Install DOLFINx Python with the typing extra, plus mypy itself (or any other type checker), e.g.:

   pip install mypy '.[typing]'
   

2. Check with mypy, e.g.:

   mypy --config-file pyproject.toml -p dolfinx
   

   The --config-file pyproject.toml is mandatory to run mypy with the correct options. The -p flag checks the built/installed package dolfinx, containing the C++ bindings and Python interface.