Cross-DAG Dependencies

Concepts covered: paCrossDagDependency, paAssetTrigger

Real production environments do not run one giant DAG. They run dozens of smaller DAGs, owned by different teams, on different cadences. Some of those DAGs depend on each other. The marketing analytics DAG reads tables produced by the orders DAG; the ML feature DAG reads tables produced by the events DAG. The dependency edge crosses a DAG boundary. Modeling that edge correctly is the difference between a system that scales across teams and one that breaks every time someone changes a schedule. Three Ways to Express a Cross-DAG Edge Why Time Offsets Fail Scheduling the downstream DAG at 3am because the upstream usually finishes by 2:45am is the cross-DAG version of the cron chain failure from the beginner tier. The bug is identical: when the upstream runs slow, the downstream still starts o

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