Basix is a finite element definition and tabulation runtime library.

Basix allows users to:
* evaluate finite element basis functions and their derivatives at a
  set of points
* access geometric and topological information about reference cells
* apply push forward and pull back operations to map data between a
  reference cell and a physical cell
* permute and transform DOFs to allow higher-order elements to be use
  on arbitrary meshes
* interpolate into a finite element space and between finite element
  spaces

Basix includes a range of built-in elements, and also allows the user
to define their own custom elements.

Basix is one of the components of FEniCSx, alongside UFL, FFCx, and
DOLFINx.