Automatic Differentiation (AD) is not only the backbone of modern deep learning but also a transformative tool across various domains such as control systems, materials science, weather prediction, 3D rendering, data-driven scientific discovery, and so on. Thanks to a mature ML framework ecosystem, powered by libraries like PyTorch and JAX, AD performs remarkably well at a component level; however, integrating these components into differentiable pipelines still remains a significant challenge. In this talk, we will provide an accessible introduction to (pipeline-level) AD, demonstrate some cool applications you can build with it, and see how to build differentiable pipelines that hold up in the real world.