I’d start by ripping the code into a graph of the smallest units—functions, classes, modules—then run a series of filters: keep only the edges that matter for flow, prune rarely‑used calls, collapse internal implementation details into “black boxes” until you hit the right level of abstraction, and layer the map so you can zoom from the entire system down to a single function. I love using AST parsers and static analysis to auto‑extract the skeleton, then feed that into a tool like D3 or Graphviz for visual tweaking, but I never let the diagram get crowded; every node has a purpose or a clear path to the next. And I’ll keep a sandbox to experiment with boundary‑pushing layouts—like radial or force‑directed—while still being pragmatic enough to finish a clean, minimalist view that doesn’t hide the hidden dependencies you’re chasing.