In this talk, I will introduce the topic of perturbative calculations in QCD for collider phenomenology and provide a brief overview of the antenna subtraction method for NNLO computations. As a cutting-edge application, I will present the calculation of the NNLO correction to diphoton-plus-jet production at hadron colliders. Finally, I will discuss recent advancements in the implementation of "generalized antenna functions," highlighting their advantages and possible future developments.