Narwhals

Narwhals is an extremely lightweight and extensible compatibility layer between dataframe libraries. It provides a unified API, largely mirroring the Polars API, enabling users to write dataframe-agnostic code that works across various backends such as pandas, Polars, cuDF, PyArrow, Dask, DuckDB, Ibis, PySpark, and SQLFrame. It is currently at version 2.18.1 and maintains an active development cycle with frequent releases, often including weekly or bi-weekly updates for bug fixes and minor enhancements.