Figure 15.4: Record and replay across the deterministic–nondeterministic seam (the dashed line): your code on the left, the model and the world on the right
Figure 15.4 Record and replay across the deterministic–nondeterministic seam (the dashed
line): your code on the left, the model and the world on the right. In record mode the
agent runs live, and an interception layer journals every crossing of the seam into the
recording. In replay mode your own code runs again—live and debuggable—but every
external call is served from that recording; the live model and tools (drawn as ghosts)
are never called, so a failure can be re-run as many times as the diagnosis needs, at no
cost and with no side effects. The two journals, in accent, are what make the snowflake a
specimen.
