  We calculate the massless unpolarized Wilson coefficients for deeply
inelastic scattering for the structure functions $F_2(x,Q^2), F_L(x,Q^2), x
F_3(x,Q^2)$ in the $\overline{\sf MS}$ scheme and the polarized Wilson
coefficients of the structure function $g_1(x,Q^2)$ in the Larin scheme up to
three--loop order in QCD in a fully automated way based on the method of
arbitrary high Mellin moments. We work in the Larin scheme in the case of
contributing axial--vector couplings or polarized nucleons. For the unpolarized
structure functions we compare to results given in the literature. The
polarized three--loop Wilson coefficients are calculated for the first time. As
a by--product we also obtain the quarkonic three--loop anomalous dimensions
from the $O(1/\varepsilon)$ terms of the unrenormalized forward Compton
amplitude. Expansions for small and large values of the Bjorken variable $x$
are provided.
