Development

Install and run checks from a source checkout:

python -m pip install ".[test]"
python -m pytest

Build distributions with python -m build. The package uses a src/ layout; installed-wheel checks must run outside the checkout. Optional R comparisons use an isolated installation of the repaired VsusP development package and do not add R to runtime dependencies.

Report defects with a small example, input shapes, package versions and the complete error message. Keep tests focused on behavior and independent calculations. Method changes need a source and a stated statistical contract.