This example shows an interactive system dynamics editor for creating and editing stock-and-flow diagrams. Users can switch between pointer, node, and link modes to add stocks, clouds, variables, valves, and flows, with editable labels and adjustable link curves. The implementation uses GoJS Diagram, LinkingTool, ClickCreatingTool, and the NodeLabelDraggingTool extension, all rendered on an HTML canvas with animation disabled. The interface highlights mode-specific toolbar buttons and tracks node creation counts to generate unique identifiers.