[firedrake] Calling PETSc within PyOP2 kernels

Hi all, I haven't experimented with this yet, but is it possible (or rather, efficient) to call PETSc routines (e.g., SNES) within a PyOP2 kernel? Because I really would like to (or need to) use PETSc's Variational Inequality solver point-wise. I have done this via petsc4py, but it seems the PyOP2 kernel is much faster in terms of accessing point wise values (which iirc is what one of you guys had told me in another thread). My only concern is if additional headers/include/library files would be needed if I wanted the C/C++ version of PETSc inside my PyOP2 kernels. Thanks, Justin