While the ab initio simulation community is structured around a few major computer codes, the field of quantum transport (a rather sizable community) does not have such common tools.

Kwant (v1.0) is a generic platform based on the theoretical framework known as "tight-binding". Kwant follows a new paradigm for numerical simulations where, instead of a monolithic program (with its associated "input" files), short programs are written in a high level language (Python). From a user perspective, the use of Kwant is very close to the natural mathematical formulation of the related theory: a Kwant system (i.e. a Hamiltonian) is described almost as the corresponding equation written on a blackboard. In a few dozen lines of code the user can realize applications as different as metallic and tunnel-effect spin valves, topological insulators, graphene, quantum Hall effect, molecular electronics, magnetic or superconducting materials, as well as any combination of the above and many other things.

Kwant is used as the base for the software codes t-Kwant (adding radio-frequency time-resolved quantum transport, in production) and ee-Kwant (adding n-body correlations, in development) which will extend our simulation capabilities to new systems and new dynamic operating regimes.