Start using Julia to do simulations of quantum systems with many interacting particles! We will write a single-core exact diagonalization code which can handle a variety of models from quantum physics, using Julia to make it readable and performant. We'll tour the Julia package ecosystem for useful packages that will help us store our results to share with others and get to the interesting physics. Then, we'll use some of Julia's parallel features to scale up our code to do many-body simulation on many-core and many-node systems in a convenient, reproducible, and fast way. You need not ever have written any Julia before. We'll use physics examples as natural motivation to explore Julia's capabilities, but no background in quantum mechanics is required. We will introduce the models as we go.