  We investigate the effects related to vortex core deformations when vortices
approach each other. As a result of these vortex core deformations, the
vortex-vortex interaction effectively acquires an attractive component leading
to a variety of vortex patterns typical for systems with non-monotonic
repulsive-attractive interaction, such as stripes, labyrinths, etc. The core
deformations are anisotropic and can induce frustration in the vortex-vortex
interaction. In turn, this frustration has an impact on the resulting vortex
patterns, which are analyzed in the presence of additional random pinning, as a
function of the pinning strength. This analysis can be applicable to vortices
in multiband superconductors or to vortices in Bose-Einstein condensates.
