Chern-Simons theory for the double of a Lie bialgebra has two natural boundary conditions, given by the Lie algebra and its dual. Using these boundary conditions for punctured disks and bordisms between them as a motivation, we are led to a definition of a nerve of Hopf algebra. We prove an equivalence between Hopf algebras and such nerves and give an application to quantization, using Drinfeld associators. Based on joint work with Pavol Ševera arXiv:1906.10616.