The current flavor landscape is populated by a wide range of tensions between experiment and theoretical determinations. After the most significant QCD-free anomalies in B Physics have gone away, there is no smoking-gun signal for the presence of New Physics in the quark sector. The root of most tensions, also between different theoretical approaches, is arguably found in the difficulty to estimate hadronic effects in a non-perturbative regime. Meanwhile, a puzzling result has arisen in the charm sector, with the groundbreaking discovery of CP violation in hadronic charm meson decays by LHCb. Even though initial Standard Model estimates seemed to point towards a smaller than measured value, the experimental measurement is extremely difficult to interpret, because there are even fewer tools to address QCD effects in the charm mass scale. In this talk I will present a data-driven calculation of the decay amplitudes of D mesons to two light mesons, based on a set of minimal assumptions and implementing the fundamental properties of the S-matrix. The determination of said amplitudes allows us to provide a prediction for the CP asymmetries measured. Some puzzling implications remain.