  This research note documents the integration of the MPI-parallel metric-based
mesh adaptation toolkit ParMmg into the solver library PETSc. This coupling
brings robust, scalable anisotropic mesh adaptation to a wide community of
PETSc users, as well as users of downstream packages. We demonstrate the new
functionality via the solution of Poisson problems in three dimensions, with
both uniform and spatially-varying right-hand sides.
