I fully agree that the broad dissemination of both established and emerging DFAs and related DFA technologies is to the benefit of the scientific community, and optimized libraries such as libxc, 751 xcfun, 745 and numgrid provide superb examples of the added value of such an approach. The impact of libxc, in particular, is noteworthy in that it provides more than 600 density functionals (LDA, GGA, and meta-GGA) to dozens of community quantum-chemistry and materials-science software packages, both open-source (e.g., PySCF, 752 Psi4, 753 Quantum ESPRESSO 754 ) and commercial (e.g., ORCA, 755 ADF, 756 Molpro 757 ). Furthermore, the library is applicable not only to Gaussian basis sets, but also to plane waves, adaptive grids, and finite-element representations.