The density-functional toolkit, DFTK for short, is a library of Julia routines for playing with plane-wave density-functional theory (DFT) algorithms. In its basic formulation it solves periodic Kohn-Sham equations. The unique feature of the code is its emphasis on simplicity and flexibility with the goal of facilitating methodological development and interdisciplinary collaboration. In about 7k lines of pure Julia code we support a sizeable set of features. Our performance is of the same order of magnitude as much larger production codes such as Abinit, Quantum Espresso and VASP. DFTK's source code is publicly available on github.
In the documentation we use very rough convergence parameters to be able to automatically generate this documentation very quickly. Therefore results are far from converged. Tighter thresholds and larger grids should be used for more realistic results.