Abstract
We present the new relativistic cosmological particle-mesh code fRevolution, based on gevolution [1], aimed at simulating non-linear structure formation in f(R) gravity. We introduce the general framework and approximation scheme, and the system of equations used to solve for the full set of gravitational perturbations. We show results for a point mass field and for cosmological simulations in the Hu-Sawicki model, and compare them to those of existing Newtonian codes. A more detailed analysis and discussion of our solutions will be carried out in a following paper [2].