Wannier-function software ecosystem for materials simulations

The description of the electronic structure in terms of extended Bloch states has made it possible to understand and calculate many properties in condensed-matter physics. However, understanding and insight often require a local description, and Wannier functions provide an exact and insightful map of extended reciprocal-space Bloch states into localized real-space orbitals. Applications range far and wide, from ultra-accurate integrations to topological invariants, and their widespread uptake by the electronic-structure community has resulted in a growing and interoperable ecosystem of methods and associated software tools. This review provides a description of this ecosystem that has now become a major instrument for the electronic-structure community in its pursuit of understanding, discovering, and designing materials.