  Proton beam dump experiments are among the most promising strategies to
search for light and feebly interacting states such as axion-like particles
(ALPs). The interpretation of these experiments is however complicated by the
wide range of ALP models and the multitude of different production and decay
channels that can induce observable signals. Here we propose a new approach to
this problem by separating the calculation of constraints and projected
sensitivities into model-independent and model-dependent parts. The former rely
on extensive Monte Carlo simulations of ALP production and decays, as well as
estimates of the detection efficiencies based on simplified detector
geometries. Once these simulations have been performed and tabulated, the
latter parts only require simple analytical rescalings that can be performed
using the public code ALPINIST released together with this work. We illustrate
this approach by considering several ALP models with couplings to Standard
Model gauge bosons. For the case of ALPs coupled to gluons we show that the
sensitivity of proton beam dump experiments can be extended significantly by
considering hadronic ALP decays into three-body final states.
