Topola is a work-in-progress free and open-source topological (rubberband) router and autorouter for printed circuit boards (PCBs). Unlike traditional maze routers, topological routers like Topola are not constrained by a grid or 45° angles, allowing for more efficient circuit board layouts (denser arrangement of components and traces, lower crosstalk, reflection, and electromagnetic interference). Topola can be used both as a GUI application and a headless command-line tool.