Nuclear theory and experiments constrain dense matter near nuclear saturation density, while neutron star observations probe the higher densities found inside stars. I will present a composition-aware model of the equation of state that brings these sources of information together and connects them to neutron star masses, radii, and tidal deformabilities. I will discuss how adding nuclear constraints changes our predictions for stellar radii and for quantities that depend on the star’s composition, including the proton fraction and the onset of direct-Urca cooling. I will then turn to stellar oscillations and compare two limiting cases: matter whose composition re-equilibrates during an oscillation, and matter whose composition remains frozen. The resulting f- and p-mode frequencies respond differently to this choice. I will close with a brief outlook on extending the model to finite temperature.