Order-fulfilment workflow net (WF-net)
A van der Aalst workflow net — a single source place and single sink place bracket an AND-split/join that runs picking and invoicing concurrently before shipping. The engine detects the WF-net structure and reports it in the SVG description.
For the process analyst
A workflow net is the Petri-net dialect business-process people actually use: exactly one source place (no incoming arcs — where a case enters) and one sink place (no outgoing arcs — where it leaves). Schematex detects this structure and notes it in the diagram's <desc>.
Concurrency by construction. split forks the order into a pick branch and an invoice branch — warehouse and finance work in parallel. ship is the AND-join: it needs both packed and billed, so an order can't ship before it's been both packed and billed. No status flags, no polling — the net enforces the ordering.
Why not a flowchart? A flowchart would draw the same boxes but couldn't express "these two run concurrently and rejoin" without ambiguity. The Petri net's token flow makes the AND-split/join unambiguous and analysable. This is the same reduction BPMN uses internally.