We investigate several transport coefficients across the phase diagram of a holographic Einstein-Maxwell-dilaton model of hot and dense QCD with $N_f=2+1$ flavors. Our results are obtained from an open-source implementation of this model in c++, publicly available as a module within the Modular Unified Solver of the Equation of State framework. This code includes a new numerical method to extract thermodynamic quantities from near-boundary asymptotics in holographic models, introduced here for the first time, to the best of our knowledge, which greatly improves numerical stability and performance in comparison to earlier implementations. Thanks to this improved technique, we are able to compute results for many realizations of our holographic model, sampled from a Bayesian posterior distribution constrained by lattice QCD results at zero chemical potential. This allows us to propagate lattice QCD error bars to predictions of transport coefficients in a wide window of temperature and baryon chemical potential, covering the crossover region, the neighborhood of the predicted critical point, and the line of first-order phase transition. The physical observables include baryon and thermal conductivities, baryon diffusion, shear and bulk viscosities, the jet-quenching parameter, the heavy-quark drag force, and Langevin diffusion coefficients. At vanishing baryon density, we compare our results to estimates extracted by the JETSCAPE Collaboration from heavy-ion data, with which we find good agreement.

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• QCD phase transitions
• Quantum chromodynamics
• Quark-gluon plasma
• Strong interaction
• Transport in heavy-ion collisions