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Branch & loop

Why you need it​

Business logic branches and loops. Those routes must themselves be durable so recovery does not guess the next action.

Code examples​

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def execute(self, context, input):
    if input.ok:
        return go_to(SuccessStep(), input)
    return go_to(self, input.retry())  # loop

Return a StepDecision that moves to another Step (or the same Step) with an input.

How Dex implements it​

The Dex interpreter records Step movements in Temporal/Cadence history and schedules the next Step execution. Loops are explicit go_to movements, not hidden polling threads.

Traditional workarounds​

Without Dex, engineers encode branches in job tables, state machines in YAML, or ad-hoc “status” enums updated by cron workers.