The need for high-precision calculations of gravitational wave signals has inspired theorists to explore new approaches. Quantum field theory techniques, such as scattering amplitudes and effective field theories, are well suited to computing observables for weak-field scattering events systematically in the post-Minkowski expansion. In this talk, I will discuss how we construct the higher-spin quantum amplitudes that feature as building blocks in scattering observables for Kerr black holes. I will present a proposal for the classical Kerr Compton amplitude to all orders in the spin, generated by implementing the appropriate classical limit.