Visualization isn't just for charts. Developers spend most of their time trying to understand existing code, which often lacks documentation about design-level concepts. Handcrafted diagrams are useful but get out of date, and traditional code search only helps if you know what words to look for. We don't navigate the real world by examining every sector of a geographic map, so why should we scan code line-by-line? This talk will showcase the past, present, and future of visual tools for automatically generating maps of code, using inspiration from older typed languages and HCI research.