The PEPC project (Pretty Efficient Parallel Coulomb Solver) is a public tree code that has been developed at Jülich Supercomputing Centre since the early 2000s. Our code is a non-recursive version of the Barnes-Hut algorithm, using a level-by-level approach to both tree construction and traversals.
FLEUR is a feature-full, freely available FLAPW (full-potential linearized augmented-plane-wave) code, based on density-functional theory. This highly precise all-electron approach is universally applicable to all atoms of the periodic table and to systems with compact as well as open structures.
Millepede II has been developed to solve the linear least squares problem with a simultaneous fit of all global and local parameters, irrespectively of the number of local parameters.
The mesoscale Hydrologic Model (mHM) is a well established hydrological model used by the scientific community. It is under active development with dozens of contributors and has an open community always interested in discussions.