Relativistic density functionals based on baryon-meson Lagrangians can

be used to describe effectively dense matter in compact stars

including hyperonic and Delta-resonance degrees of

freedom. These can be supplemented with a first-order phase transition

to quark matter at high densities to describe hybrid compact stars.

I will discuss how the mass-radius and tidal deformability inferences

from electromagnetic and gravitational wave observations constrain the

current models of hypernuclear and hybrid stars. I will briefly review

recent results on the bulk viscosity of dense nucleonic matter in hot

compact stars, which emerged in recent years as the leading dissipative

channel in binary-neutron star merger simulations.