Understand lowering: how a graph becomes code

Your graph is not walked node by node at run time. Before it runs, it is lowered: the whole graph is translated into ordinary code, a single class with one async handler, which is then compiled and runs exactly like a script written by hand.

"Lowering" is the compiler word for rewriting something high level (your visual flow) into something lower level (the code that actually executes). One node might lower to a single line; a loop or a parallel branch lowers to the matching code structure.

Why it matters

Because the graph becomes real code, its cost is real code's cost. A node that looks small on the canvas can still lower to an expensive call, and two nodes wired in sequence run in sequence in the generated code. Ordering and branching, not how tidy the canvas looks, decide how much work actually happens.

See it for yourself

The desktop companion's Execution plan panel shows, for each step, the exact code that step lowers to along with its relative cost. It reads like a database query planner: use it to spot the steps that dominate a flow before you reach for Parallel or a Timeout.