Sure; this isn't directed at step functions, but in general, if you have your business logic (state machine) in a declarative format, albeit non-programming lan

Sure; this isn't directed at step functions, but in general, if you have your business logic (state machine) in a declarative format, albeit non-programming language (e.g., JSON), then that can potentially make it even more testable than a hand-written, informally-specified state machine in code. Since all of the states/transitions are consistently and declaratively specified, you can iterate through them, build up a directed graph in code, and unit/integration/E2E test them however you'd like. Without that strict declarative "DSL", you would need to figure that out otherwise (requires much more effort), and you're bound to miss coverage on states/transitions, especially if the logic changes.