How can you merge or split flows dynamically?
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Most automation platforms let you build flows with conditional branching, where a subscriber takes different paths based on their behavior or attributes. Dynamic merging and splitting is that idea extended to handle real-world complexity.
Splitting means a single flow branches at a decision point. A subscriber enters your welcome sequence, and on day 3 the flow checks: did they purchase? Yes path goes to a post-purchase sequence. No path continues the nurture sequence. Each branch handles a different customer state independently from that point on.
Merging is the reverse. Multiple separate paths converge at a shared continuation. Different acquisition sources (organic search, paid ads, referral) might each have their own onboarding sequences, but at day 14 they all merge into the same ongoing newsletter cadence. This simplifies long-term maintenance. You're not maintaining three parallel sequences indefinitely.
What makes this "dynamic" rather than just "branching" is when conditions are evaluated. A dynamic split checks subscriber state at the moment the branch decision is made, not at the moment they entered the flow. Someone who entered as a free-plan user might have converted to paid mid-sequence. A dynamic check at the branch point catches that. A static branch based on entry state wouldn't.
Platform support varies. Most modern ESPs handle splits fine. True dynamic merging, where you pull a subscriber out of one active flow and inject them into another mid-sequence, is less common. It often requires custom configuration, webhook-based triggers, or middleware like Zapier. Check your platform's documentation before designing a flow that depends on this.
One practical note: Clean segmentation data at the entry point makes split logic more reliable. If subscriber attributes are stale or miscategorized going in, they'll be misrouted at every branch decision downstream. Garbage in, wrong path out. A quick list validation before building complex branched flows is worth it.
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