DFTB+ general package for performing fast atomistic simulations

Semiempirical Extended Tight-Binding Program Package

Interface enabling use of ANI-style, and other NN-IPs in the Amber molecular dynamics software suite. Works with both Amber engines, sander and pmemd.

CREST - A program for the automated exploration of low-energy molecular chemical space.

A Kinetic Monte Carlo super-Lattice code designed to simulate with atomic resolution the kinetics of processes (e.g., PVD, CVD, laser annealing) involving elements, alloys and compounds characterized by the sp3 bond symmetry.

Atomsk: A Tool For Manipulating And Converting Atomic Data Files -

Nagoya Atomistic-simulation Package (NAP). Why don't you take a NAP? ;)

FLAME: a library for atomistic modeling environments

Program to determine the minimal RMSD between two atomic configurations

Cassandra is a Monte Carlo package to conduct atomistic simulations.

Fully loaded atomistic modeling environment

Spring

Modular package for atomistic simulations based on Python.