The lensing convergence measurable with future CMB experiments will be highly correlated with the clustering of galaxies that will be observed by deep imaging surveys such as LSST. I will discuss prospects for using that cross-correlation signal to constrain inflation models (fnl), the growth of structure as a function of redshift, and the sum of neutrino masses without optical depth information. A key limitation of such large-scale structure analyses is that dark matter halos and the galaxies within them only form at peaks of the dark matter density distribution, which is challenging to model. I will present recent work on this, where we found that a new basis of IR-resummed operators successfully describes simulated halos at the field level over a surprisingly wide range of scales.