  Wannier interpolation is a powerful tool for performing Brillouin zone
integrals over dense grids of $\mathbf{k}$ points, which are essential to
evaluate such quantities as the intrinsic anomalous Hall conductivity or
Boltzmann transport coefficients. However, new physical problems and new
materials create new numerical challenges, and computations with the existing
codes become very expensive, which often prevents reaching the desired
accuracy. In this article, I present a series of methods that boost the speed
of Wannier interpolation by several orders of magnitude. They include a
combination of fast and slow Fourier transforms, explicit use of symmetries and
recursive adaptive grid refinement among others. The proposed methodology has
been implemented in the new python code WannierBerri, which also aims to serve
as a convenient platform for the future development of interpolation schemes
for novel phenomena.
