  We combine the fully anisotropic Migdal-Eliashberg theory with
electron-phonon interpolation based on maximally-localized Wannier functions,
in order to perform reliable and highly accurate calculations of the
anisotropic temperature-dependent superconducting gap and critical temperature
of conventional superconductors. Compared with the widely used McMillan
approximation, our methodology yields a more comprehensive and detailed
description of superconducting properties, and is especially relevant for the
study of layered or low-dimensional systems as well as systems with complex
Fermi surfaces. In order to validate our method we perform calculations on two
prototypical superconductors, Pb and MgB$_2$, and obtain good agreement with
previous studies.

Superconductivity