Narwhals is an extremely lightweight and extensible compatibility layer between
dataframe libraries!
- Full API support: cuDF, Modin, pandas, Polars, PyArrow
- Interchange-level support: Ibis, Vaex, anything else which implements the
  DataFrame Interchange Protocol

Seamlessly support all, without depending on any!
- Just use a subset of the Polars API, no need to learn anything new
- Zero dependencies, Narwhals only uses what the user passes in so your library
  can stay lightweight
- Separate lazy and eager APIs, use expressions
- Support pandas' complicated type system and index, without either getting in
  the way
- 100% branch coverage, tested against pandas and Polars nightly builds
- Negligible overhead, see overhead
- Let your IDE help you thanks to full static typing, see typing
- Perfect backwards compatibility policy, see stable api for how to opt-in