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Durable variables

Why you need it​

Long-running work needs typed state that survives restarts and is readable across Steps and RPCs — without inventing a side database schema for every Flow.

Code examples​

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status = Attribute("status", str)

def execute(self, context, input):
    status.set(context, "running")
    return go_to(next_step, input)

Attributes are declared on the Flow and read/written from Steps and RPCs.

How Dex implements it​

Dex stores Attributes as durable Flow state (optionally indexed). Workers receive Attribute values when executing WaitFor/Execute/RPC; updates are committed with Step decisions.

Traditional workarounds​

Teams typically glue Redis/SQL + optimistic locking + custom APIs, then rehydrate state on every resume.