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+# Development Notes
+
+This directory preserves internal planning documents created while migrating the earlier
+PyGPLA development code into the current Python package. They are retained as a historical
+record of the project’s design and migration process, not as current user documentation.
+For current information, see the repository `README.md` and the documentation under `docs/`.
+
+## Implemented
+
+The planned `src/pygpla` package structure, layered core/preprocessing/statistics API,
+configuration objects, supported simulations, Hatchling packaging, tests, CI, Sphinx
+documentation, and PyPI distribution were implemented.
+
+## Deviations
+
+Unsupported or unused planned components—including multifrequency simulations, utility and
+statistics-summary modules, bundled datasets, and a CLI—were not retained. Sphinx was chosen
+instead of MkDocs, Python support starts at 3.10, and automated regression fixtures against
+MATLAB reference outputs remain future work.