  We develop a discrete fermion approach for modelling the strong interaction
of an arbitrary system interacting with continuum electronic reservoirs. The
approach is based on a pseudo-fermion decomposition of the continuum bath
correlation functions, and is only limited by the accuracy of this
decomposition. We show that to obtain this decomposition one can allow for
imaginary pseudo-fermion parameters, and strong damping in individual
pseudo-fermions, without introducing unwanted approximations. For a
non-interacting single-resonant level, we benchmark our approach against an
analytical solution and an exact hierachical-equations-of-motion approach. We
also show that, for the interacting case, this simple method can capture the
strongly correlated low-temperature physics of Kondo resonance.
