satcand applies theoretical constraints of orbital stability and tidal migration to KOI exomoon candidates. The package can evaluate the tidal migration within a Sun-Earth-Moon system, plot angular velocity over time, and calculate the migration time scale (T1) and the total migration time scale, among other things. In addition to the theoretical constraints, observational constraints can be applied.

GRIT (Gravitational Rigid-body InTegrators) simulaties the coupled dynamics of both spin and orbit of N gravitationally interacting rigid bodies. The code supports tidal forces and general relativity correction are supported, and multiple schemes with different orders of convergences and splitting strategies are available. Multiscale splittings boost the simulation speed, and force evaluations can be parallelized. In addition, each body can be set to be a rigid body or just a point mass, and the floating-point format can be customized as float, double, or long double globally.